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 Stilbite crystals      Flourite



                                                            Identify That Rock!: A
  Tourmaline Crystals:                   Hemimorphite in
                                                            Basic Tutorial
   Red, Black & Green                        Scoria

                                                            Created by Shelby Raymond, Skeena Storm Stones

                                                            Please do not copy or distribute without the
                                                            express permission of Shelby Raymond.
   Apache Tear in
      Perlite
                           Variety of Igneous Rocks
                                                            MATERIALS and TOOLS :
                                                                 Random selection of stones
                                  Vanadinite
                                                            Rock ID Kit:
                                                                One piece of shatter proof glass (about 1-2
                                                                 inches in length, with no sharp edges, at
                                                Grossular        least 1/8 of an inch thick)
   2 variety of Topaz                            Garnet         1-ceramic, unglazed white tile (2x2” square)
                                                                1-ceramic, unglazed black tile (2x2” square)
                           Gypsum Crystals
                                                                Jeweler’s Loupe (usually 10x magnification)
                                                                Steel nail or small fragment of steel
                                                                Vinegar in a small vial
                                                                Small eyedropper
  Fibrous Malachite          Wulfenite         Molybdenum
                                                                Container to hold all of the above
                                                                Notepad to record your findings
                              Agates & jaspers from Haida       Paper or cloth towels to wipe up spills
                              Gwaii (a.k.a. The Queen
                              Charlotte Islands, British        Container to hold your rock samples while
                              Columbia, Canada)                  you are working with them
                                                                Table cover – I use pieces of felt to cover my
                                                                 table. I strongly suggest this so you can
                                                                 avoid scratching your furniture. 

                                                            Legal Stuff: By using and viewing the content of this
                                                            tutorial, you agree not to distribute, lend or copy any
                                                            portion of this document; to not mass produce this
                                                            document and to hold Skeena Storm Stones and
                                                            Shelby Raymond and Skeena Rocks! free of any and all
                                                            claims. This content is provided AS IS. If you wish to
                                                            use this in a classroom setting, please contact the
                                                            author for written permission prior to use.
                                                            *Children should always be supervised by a responsible
                                                            adult.

                                                            Whew! Got it all? Agree to the terms? Then please,
                                                            read on, be safe and have FUN!

                                                            If you have questions, please do not hesitate to contact
                                                            me.


River stones from on the shore of the Skeena River near
Terrace, British Columbia, Canada
Identify that Rock – Updated 12-01-09                Copyright 2008 Shelby Raymond, Skeena Storm Stones        Page: 2



                                                                  STEP 1: ROCK TALK
                                 1
                                                                  We’ll start with a couple of definitions so that
                    7                                   2         we are all talking the same language!



                            8                                           3 Main Categories of Rock:
            6                                                             1. Igneous
                                                        3                 2. Sedimentary
                                                                          3. Metamorphic
                                                                  Igneous
                                                                          Igneous rocks are formed when melted
                    5                                                     rock, from deep inside the earth or a
                                                                          volcano, makes it way to the surface
                                                                          and then cools quickly. e.g. granite
                                             4                            and obsidian
     (clockwise from top center): (1)gabbro, (2)diorite,
     (3)scoria, (4)basalt, (5)pumice, (6)granite, (7)tuff, (8)            2 Types of Igneous Rocks:
     obsidian                                                             a. Intrusive = magma that cools
                                                                             beneath the surface (i.e. granite)
                                                                          b. Extrusive = magma that cools
                                                                             above the surface, i.e. lava, basalt

                                                                  Sedimentary
                                                                          Sedimentary rocks are formed when
                                                                          stuff piles up – like stones, shells,
                                                                          plant material, etc. As these items
                                                                          pile up on top of one another, they put
                                                                          pressure on the bottom layer, which
                                     9
             19                                                           causes the items to stick together –
                                                                          eventually forming a solid rock. Quite
                    18                             10                     frequently you’ll be able to see the
                                     20
                                                                          layering effect.

                                17                 11                     Sedimentary rocks can be used in
                                                                          making jewelry, however, most are
                    16                      13
                                                                          very soft and need to be stabilized or
                                                         12               placed in epoxy to protect them from
                                14
                                                                          every day bumps and even weather!

                                                                          You will find fossil evidence in
                                15                                        sedimentary rocks more frequently
                                                                          than the other two types. This is
                                                                          because the heat involved in the
                                                                          creation of igneous stones usually
     (clockwise from top, center) (9)oil shale, (10)breccia,
     (11)shale, (12)conglomerate, (13)limestone, (14)arkose,              destroys the object. Heat and pressure
     (15)lignite coal, (16)fossiliferous limestone, (17)                  frequently destroy potential fossil
     brachiopod limestone,(18) travertine, (19)sandstone,                 objects during the creation of
     (20)calcareous tufa                                                  metamorphic stones.
Identify that Rock – Updated 12-01-09                Copyright 2008 Shelby Raymond, Skeena Storm Stones          Page: 3


                                                                    Metamorphic
                                                         22            A metamorphic rock is created when other
                                     21                                rocks, igneous or sedimentary, are heated
                                                                       or squeezed. This usually happens inside
                   28                                                  the earth and the heat and squeezing
                                                                       makes the rocks form into something that
                                                   23                  can be completely different. You can see
                          29                                           this effect in some stones or even on the
       27                                                              sides of some mountains when there is a
                                                                       “folding” effect. e.g. slate, gneiss

                                                                       The crystals in metamorphic rocks are still
                                          25                   24
              26                                                       somewhat easy to see, though they are
                                                                       more finely grained than their
                                                                       sedimentary counterparts.
                                                                       i.e. limestone  marble,
                                                                       clusters of quartz quartzite

                                                                       To the left are pictures of some of the
                                                                       commonly found metamorphic rocks.
       (Clockwise from top, center): (21)hornfels, (22)gneiss,
      (23) marble, (24)phyllite, (25) quartzite, (26) slate, (27)
           anthracite coal, (28) phyllite, (29) amphibolite


                                                                    Breaking Up is Hard to Do: Cleavage &
                                                                    Fracture
                                                                       Another identity helper is to find out the
                                                                       shapes formed on a rock’s surface when
                                                                       that rock breaks.

                                                                       To the left is a picture of Mica. This is
                                                                       commonly found, especially in granitic
                                                                       rocks. Mica breaks into layers of thin
                                                                       sheets. Dark Mica, like you see here, is
                                                                       dark because it contains iron &
             Mica var. Biotite– Perfect Cleavage
                                                                       magnesium. You can use mica in jewelry,
                                                                       but it would be best supported in a gel or
                                                                       epoxy because it is extremely fragile. As a
                                                                       component in another stone it doesn’t
                                                                       usually pose problems, but the stone may
                                                                       be more likely to fracture in mica planes.



                                                                    Common Types of Fracture/Cleavage:

                                                                           Perfect Cleavage – as in mica, thin
                                                                           sheets along a plane

                                                                           Conchoidal fracture-the break
         Snowflake obsidian – conchoidal fracture
                                                                           curves, kind of like a seashell or bowl
                                                                           shape could fit into the curve of the
                                                                           fracture.
Identify that Rock – Updated 12-01-09                 Copyright 2008 Shelby Raymond, Skeena Storm Stones           Page: 4


                                                                       Crystal:
                                                                             A crystal is the form a mineral takes
                                                                             on as it grows. You have probably
                                                                             seen crystals such as rose quartz or
                                                                             amethyst. The biggest crystals are
                                                                             usually found in areas where there is
                                                                             room to grow – crevices and caves. Do
                                                                             a search on the internet for the giant
                                                                             selenite gypsum crystals found in the
                                                                             Naica mine, Cave of Swords, south of
                                                                             Chihuahua City, Mexico – you WILL be
     Amethyst is a type of Quartz (both pictured above) and is
                                                                             amazed!
     considered a semi-precious stone.



                         To the left is a fluorite crystal; fluorite   Gem:
                         crystals are octahedral (they have 8                 It’s kind of challenging to define what
                         sides). Most minerals have a “typical”               a gem is. Usually gems are the hardest
                         crystal formation and this can help you
                                                                              stones, such as diamonds and ruby -
                         identify stones.
                                                                              although opals give lie to that
                                                                              definition! Gems are also usually
                                                                              formed in igneous or metamorphic
                                                                              rock. They are also usually quite rare
                                                                              – in fact, the rarer the stone, the more
               Grossular garnet, var. Hessonite in
                                                                              valuable it tends to be. Gems are
             metamorphosed impure limestone matrix
                                                                              usually brighter and contain fewer
                                                                              impurities than their semi-precious
                                                                              cousins.

                                                                       Mineral:
                                                                             Minerals are the building blocks of the
                                                                             universe. Most rocks are made up of
                                                                             minerals. Each mineral has a clearly,
                                                                             scientifically defined chemical content
                                                                             and the atoms are put together,
                                                                             arranged, in a very specific way.
                                   garnet (gem)




     MOHS Scale of Hardness                                            MOHS Scale of Hardness
       1. Talc
       2. Gypsum                                                       The MOHS Scale of Hardness is a quick and
       3. Calcite                                                      easy guide to help you figure out how hard a
       4. Flourite                                                     rock is and it also aids you in identifying the
       5. Apatite (turquoise, lapis lazuli)                            rock. The softest stone is Talc at number 1,
       6. Orthoclase feldspar (epidote,                                with diamond being the hardest at number
           labradorite)                                                10.
       7. Quartz (amethyst, aventurine)
       8. Topaz (spinel, zirconia)                                     Harder minerals (higher numbers on the
       9. Corundum (ruby, sapphire)                                    scale) will scratch softer ones (the ones with
       10. Diamond                                                     smaller numbers). i.e. quartz will scratch
                                                                       orthoclase, apatite, fluorite, calcite, gypsum
     Quickie MOHS                                                      and talc, but it will not scratch topaz,
        2.5 = fingernail                 5.5 = pocket knife            corundum or diamond!
        3.5 = penny                      6.5 = steel file
Identify that Rock – Updated 12-01-09                          Copyright 2008 Shelby Raymond, Skeena Storm Stones          Page: 5



                                            This is a great book                  STEP 2: KNOW YOUR PLACE
                                            that was written by a
                                            local geologist. With                   Learn about the area in which you live, or
                                            this knowledge in                       places you can easily visit. Usually it’s
                                            hand, combined with                     possible to find a rockhound group,
                                            information on what                     lapidary or mineral society. They are
                                            formations are likely                   wonderful sources of information.
                                            to contain specific
                                            stones, my rock hunts                   Government websites also have
                                            are usually                             information on the geography and
                                            successful.                             geology of most regions. It’s easy to
                                                                                    download maps or brochures that detail
                                                                                    what kinds of minerals and rocks may be
                                                                                    nearby.

                                                                                    Take a class in geography, geology or
                                                                                    rockhounding. Not only will you meet
                                                                                    people with similar interests, but you may
                                                                                    also learn of some new collecting sites!


                                                                                  STEP 3: MIND YOUR MANNERS
                                                                                    Whenever you are out looking for rocks,
     Map of world showing the distribution of major deposits plotted on digital     have a rockhounding buddy with you and
     elevation model with draped geology from Geological Survey of Canada,          make sure others know where you are
       Open File 2915d, 1995.Data from the synthesis of ore deposits. Data
               plotted and diagrams prepared by W.D. Goodfellow.
                                                                                    going and approximately when you will
                                                                                    return.

                                                                                    Always get permission before entering
                                                                                    private land. When in doubt, check with
                                                                                    local authorities.

                                                                                    Be careful. Take a first aid kit and know
                                                                                    the local numbers for emergency
                                                                                    assistance. Avoid active slide areas – no
                                                                                    matter how great the “find”! Remember
                                                                                    that caves can be dangerous –only enter
                                                                                    with a trained spelunker.

                                                                                    Know the type of rocks and minerals you
                                                                                    will encounter beforehand. You want to
                                                                                    avoid handling dangerous rocks and
                                                                                    minerals. Galena (grey and very heavy)
                                                                                    and sulfur (usually BRIGHT yellow) should
         The Skeen River, Terrace, British Columbia, Canada                         only be handled with gloved hands.

                                                                                    Finally, leave the places you rockhound as
                                                                                    you found them. Pick up litter and debris;
                                                                                    fill holes, respect landowners and others
                                                                                    who use the area.
Identify that Rock – Updated 12-01-09    Copyright 2008 Shelby Raymond, Skeena Storm Stones         Page: 6


                                                     4. WHERE IN THE MOHS IS IT?
                                                        By placing a rock within the MOHS scale, you
                                                        are able to estimate the hardness of that
                                                        rock. This can be helpful in identifying a
                                                        stone.

                                                        When testing for MOHS, you don’t need to
                                                        scratch with all of your strength. Using
                                                        normal pressure, like what you use when you
                                                        are writing with a pencil, scrape the testing
                                                        stone or tool across your rock.

                       zircon                           Repeat this until your stone is scratched. If
                                                        your stone is special, don’t use these tests, or
                                                        do them in an area you won’t notice.

                                                     5. LOOKS DO COUNT
                                                        Colour is extremely important in the
                                                        identification of many rocks. Once you have
                                                        seen the green of malachite you will always
                                                        remember it.

                                                        The appearance, or luster, of rocks is also
                                                        helpful in their identification. Some will look
                                                        some will look dull like chalk (slate has a
                                                        “chalk” dullness), glassy – like a drinking
                 Fibrous malachite                      glass (think of quartz or obsidian); greasy
                                                        (graphite has a greasy feel); silky like silk
                                                        (asbestos types look silky).




                                                     6. IT AIN’T HEAVY IT’S JUST TALC
                                                       When you look in rock identification books,
                                                       they usually provide the specific gravity (SG)
                                                       of a rock or mineral. This is basically a
                                                       comparison of the mineral or rock compared to
                                                       the weight of an equal volume of water. Water
                                                       has a SG of 1.

   The mineral sample above is “galena”. This is a     Rocks that seem heavy for their size usually
    toxic mineral you should avoid handling with       have a high density. The density of a stone
      bare hands. It, and lead, are noticeably         generally refers to how tightly packed the
             “heavier” than most rocks.                crystals are. i.e. Galena has an SG of~7.4-
                                                       7.6 and is quite dense, whereas sulfur weighs
                                                       in at ~2-2.1 and isn’t nearly as dense as the
                                                       galena.
Identify that Rock – Updated 12-01-09      Copyright 2008 Shelby Raymond, Skeena Storm Stones          Page: 7


   Common Streak Colours                              7. STREAKING IS ALLOWED
   Limonite = Yellow-brown                                When it comes to rock & mineral identification
   Hematite = Red-brown                                   – streaking is allowed! In fact, it is
   Gold = yellow                                          encouraged! This is where the ceramic streak
   Galena = grey                                          plates in your kit will come in handy.
   Graphite = black
   Pyrite = black                                         To find out what colour streak your rock has,
   Magnetite = black                                      you will scratch it across both plates – the
   Chalcopyrite = black                                   white and the black unglazed ceramic.
                                                          Sometimes you’ll be surprised, as the streak
   Below are a couple of examples where knowing           left by a stone may be completely different
   the streak colour of stones can be quite useful.       than the colour of its actual physical
                                                          appearance! Minerals harder than the plate
   The colour streak for gold is yellow and Fool’s        will not leave a streak.
   Gold (Pyrite) has a red streak!
                                                          It is important to note that most silicates
   Hematite (a popular jewelry making stone) has          (most of the stones we use in jewelry fall into
   a read streak, while galena (a toxic stone with        the silicate class) have a white streak and this
   similar outward features) has a grey streak.           may not help identify them.



                                                      8. POP, POP, FIZZ, FIZZ
                                                          Next we will play with the vinegar and the
                                                          nail. This tiny experiment can help you find
                                                          out if there is calcite (calcium carbonate)
                                                          present in your rock. Calcite is one of the
                                                          most common minerals on earth - ~4% of the
                                                          earth’s crust (by weight).

                                                          Holding your rock firmly in your hand, scratch
                                                          the surface with either a pocket knife or the
                                                          nail in your ID kit. If you can’t scratch up a
                                                          little bit of “shavings”, you definitely don’t
                                                          have a rock that contains calcite.

                                                          Now, drop one drop of vinegar onto the pile of
                                                          “shavings”. If it fizzes, calcite is present. If it
                                                          doesn’t, you probably don’t have calcite in
                                                          your rock.

                                                          Some folks use Muriatic (hydrochloric) acid in
                                                          10% dilution for this test. Because Muriatic
                                                          acid can be extremely dangerous to handle,
   Rocks that contain calcium carbonate:                  it’s not something I suggest. Handling
       Calcite (it IS calcium carbonate!)                Muriatic acid requires special training and
       Limestone                                         hazard containment procedures.
       Marble (it is compressed limestone)
       Carbonatite                                   Calcite can be the “glue” in:
       Mexican Onyx                                      Sandstone
       Iceland Spar                                      Slate
Identify that Rock – Updated 12-01-09                      Copyright 2008 Shelby Raymond, Skeena Storm Stones         Page: 8


                                                                      THANK YOU!

                                                                      I hope this tutorial will help you identify some of
                                                                      the basic stones in your world. Remember, even
                                                                      experts have times when they can’t identify a
                                                                      rock specimen and need have it examined under
                                                                      a special microscope or have a chemical analysis.

                                                                                               The best way to learn about
   The rock above is the one we’ll identify in this tutorial.                                  rocks is to meet with other
                                                                                               enthusiasts and explore as
   9. WHAT IS IT?                                                                              many different stones as
   Take out your first rock and give it a good look-                                           possible. One of the best
   over. You might already have a good idea if you                                             ways I learn about stones is
   are using a rockhound guide or map of deposits.                                             through The Mineral of the
                                                                                               Month Club.
   Can you tell if it is Igneous, Sedimentary or
   Metamorphic?                                                                               I wish you a future filled
      My sample at left is Igneous – it looks                                                 with fascinating and
      like it cooled quickly because I don’t see                                              beautiful rocks and
      any specific crystal formations.                                                        minerals! In my humble
                                                                      opinion, even a plain old basalt river rock is
   What kind of fracture or cleavage does it have?                    gorgeous enough to be used in making jewelry;
      The “fractures” are conchoidal. With my                         in fact it is one of my favourites!
      jeweler’s loupe I can see little “dishes”
      or bowl shapes.

   Where in the MOHS is this rock? Now we’ll use
   the MOHS scale to test my rock. Will #1 on the
   MOHS scale scratch it?
   No
       In fact, this stone isn’t scratched until
       we get to #8 on the MOHS scale. I tested
       it with zircon and it does scratch my
       stone. I also dragged my stone across
       the glass plate, just a little pressure is
       necessary. It scratched the plate. Now I
       know my stone is softer than #9.
                                                                                                   For comments or
   I tried scratching it with my nail and couldn’t get
                                                                                                   questions, please go to
   any “shavings”.
                                                                                                   JewelryLessons.com
        This tells me two things: 1. I don’t have
        calcium carbonate present in my rock
        and my rock is harder than the knife so                                                    Please do not distribute
        the MOH is greater than~5.5.                                                               or copy.

   I know by observation that my stone is pink in                     Copyrights 2008, Shelby Raymond, Skeena Storm
   appearance, as well as translucent and glassy. I                   Stones, http://skeenastormstones.com
   also know that the area is known for quartz;
   specifically rose quartz is frequently found. I                    All photos contained within this tutorial are the
   looked in my mineral book and sure enough,                         exclusive property of Shelby Raymond.
   everything matches up to rose quartz.
       With all of the information I now have, I                      Map photo on page 5 is the property of the
       know that my stone is rose quartz.                             Government of Canada.
Identify that Rock – Updated 12-01-09    Copyright 2008 Shelby Raymond, Skeena Storm Stones     Page: 9


SUGGESTED REFERENCES

    A Field Guide to the Identification of Pebbles. Eileen Van der Flier-Keller. Harbour
     Publishing.2006. ISBN-10:1-55017-395-2 (This is an AWESOME little reference for identifying river
     rocks and “regular” stones!)

    Rocks & Minerals. DK Publishing.2003. ISBN-13: 978-0-7894-9587-7

    Guide to Minerals, Rocks & Fossils. A.C. Bishop, A.R. Woolley, W.R. Hamilton. Firefly Books.
     ISBN: 1-55407-054-6

    National Audobon Society - First Field Guide: Rocks and Minerals. Edward Ricciuti, Margaret
     W. Carruthers. Scholastic Inc. 1998. ISBN: 0-590-0584-8

    Mineral of the Month Club. http://mineralofthemonthclub.org (Please tell them Shelby Raymond
     referred you! Thanks.)

    The Mineral and Locality Database. http://mindat.org

    The Practical Geologist: The introductory guide to the basics of geology and to collecting
     and identifying rocks. Dougal Dixon. Raymond L. Bernor, Editor. Simon and Schuster, Fireside.
     1992. ISBN-13: 978-0-671-74697-1

    Amethyst Galleries' Mineral Gallery, http://mineral.galleries.com/

    CANADA ROCKS: The Geologic Journey. Nick Eyles, Andrew Miall. Fitzhenry & Whiteside. 2007.
     ISBN: 978-1-55041-860-6

    The Practical Geologist. Dougal Dixon. Raymond L. Bernor, Editor. 1992. Simon and
     Schuster/Fireside. ISBN: 978-0-671-74697-1




Disclaimer: Caution is urged while working with rocks and minerals. Children should always be supervised
by a responsible adult. Shelby Raymond and Skeena Storm Stones are not liable for accidents, injuries or
losses that may be incurred by use of this tutorial.

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Identify Rocks And Minerals Shelby Raymond Rev12 1 09 My Copy

  • 1.  Stilbite crystals Flourite Identify That Rock!: A Tourmaline Crystals: Hemimorphite in Basic Tutorial Red, Black & Green Scoria Created by Shelby Raymond, Skeena Storm Stones Please do not copy or distribute without the express permission of Shelby Raymond. Apache Tear in Perlite Variety of Igneous Rocks MATERIALS and TOOLS :  Random selection of stones Vanadinite Rock ID Kit:  One piece of shatter proof glass (about 1-2 inches in length, with no sharp edges, at Grossular least 1/8 of an inch thick) 2 variety of Topaz Garnet  1-ceramic, unglazed white tile (2x2” square)  1-ceramic, unglazed black tile (2x2” square) Gypsum Crystals  Jeweler’s Loupe (usually 10x magnification)  Steel nail or small fragment of steel  Vinegar in a small vial  Small eyedropper Fibrous Malachite Wulfenite Molybdenum  Container to hold all of the above  Notepad to record your findings Agates & jaspers from Haida  Paper or cloth towels to wipe up spills Gwaii (a.k.a. The Queen Charlotte Islands, British  Container to hold your rock samples while Columbia, Canada) you are working with them  Table cover – I use pieces of felt to cover my table. I strongly suggest this so you can avoid scratching your furniture.  Legal Stuff: By using and viewing the content of this tutorial, you agree not to distribute, lend or copy any portion of this document; to not mass produce this document and to hold Skeena Storm Stones and Shelby Raymond and Skeena Rocks! free of any and all claims. This content is provided AS IS. If you wish to use this in a classroom setting, please contact the author for written permission prior to use. *Children should always be supervised by a responsible adult. Whew! Got it all? Agree to the terms? Then please, read on, be safe and have FUN! If you have questions, please do not hesitate to contact me. River stones from on the shore of the Skeena River near Terrace, British Columbia, Canada
  • 2. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 2 STEP 1: ROCK TALK 1 We’ll start with a couple of definitions so that 7 2 we are all talking the same language! 8 3 Main Categories of Rock: 6 1. Igneous 3 2. Sedimentary 3. Metamorphic Igneous Igneous rocks are formed when melted 5 rock, from deep inside the earth or a volcano, makes it way to the surface and then cools quickly. e.g. granite 4 and obsidian (clockwise from top center): (1)gabbro, (2)diorite, (3)scoria, (4)basalt, (5)pumice, (6)granite, (7)tuff, (8) 2 Types of Igneous Rocks: obsidian a. Intrusive = magma that cools beneath the surface (i.e. granite) b. Extrusive = magma that cools above the surface, i.e. lava, basalt Sedimentary Sedimentary rocks are formed when stuff piles up – like stones, shells, plant material, etc. As these items pile up on top of one another, they put pressure on the bottom layer, which 9 19 causes the items to stick together – eventually forming a solid rock. Quite 18 10 frequently you’ll be able to see the 20 layering effect. 17 11 Sedimentary rocks can be used in making jewelry, however, most are 16 13 very soft and need to be stabilized or 12 placed in epoxy to protect them from 14 every day bumps and even weather! You will find fossil evidence in 15 sedimentary rocks more frequently than the other two types. This is because the heat involved in the creation of igneous stones usually (clockwise from top, center) (9)oil shale, (10)breccia, (11)shale, (12)conglomerate, (13)limestone, (14)arkose, destroys the object. Heat and pressure (15)lignite coal, (16)fossiliferous limestone, (17) frequently destroy potential fossil brachiopod limestone,(18) travertine, (19)sandstone, objects during the creation of (20)calcareous tufa metamorphic stones.
  • 3. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 3 Metamorphic 22 A metamorphic rock is created when other 21 rocks, igneous or sedimentary, are heated or squeezed. This usually happens inside 28 the earth and the heat and squeezing makes the rocks form into something that 23 can be completely different. You can see 29 this effect in some stones or even on the 27 sides of some mountains when there is a “folding” effect. e.g. slate, gneiss The crystals in metamorphic rocks are still 25 24 26 somewhat easy to see, though they are more finely grained than their sedimentary counterparts. i.e. limestone  marble, clusters of quartz quartzite To the left are pictures of some of the commonly found metamorphic rocks. (Clockwise from top, center): (21)hornfels, (22)gneiss, (23) marble, (24)phyllite, (25) quartzite, (26) slate, (27) anthracite coal, (28) phyllite, (29) amphibolite Breaking Up is Hard to Do: Cleavage & Fracture Another identity helper is to find out the shapes formed on a rock’s surface when that rock breaks. To the left is a picture of Mica. This is commonly found, especially in granitic rocks. Mica breaks into layers of thin sheets. Dark Mica, like you see here, is dark because it contains iron & Mica var. Biotite– Perfect Cleavage magnesium. You can use mica in jewelry, but it would be best supported in a gel or epoxy because it is extremely fragile. As a component in another stone it doesn’t usually pose problems, but the stone may be more likely to fracture in mica planes. Common Types of Fracture/Cleavage: Perfect Cleavage – as in mica, thin sheets along a plane Conchoidal fracture-the break Snowflake obsidian – conchoidal fracture curves, kind of like a seashell or bowl shape could fit into the curve of the fracture.
  • 4. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 4 Crystal: A crystal is the form a mineral takes on as it grows. You have probably seen crystals such as rose quartz or amethyst. The biggest crystals are usually found in areas where there is room to grow – crevices and caves. Do a search on the internet for the giant selenite gypsum crystals found in the Naica mine, Cave of Swords, south of Chihuahua City, Mexico – you WILL be Amethyst is a type of Quartz (both pictured above) and is amazed! considered a semi-precious stone. To the left is a fluorite crystal; fluorite Gem: crystals are octahedral (they have 8 It’s kind of challenging to define what sides). Most minerals have a “typical” a gem is. Usually gems are the hardest crystal formation and this can help you stones, such as diamonds and ruby - identify stones. although opals give lie to that definition! Gems are also usually formed in igneous or metamorphic rock. They are also usually quite rare – in fact, the rarer the stone, the more Grossular garnet, var. Hessonite in valuable it tends to be. Gems are metamorphosed impure limestone matrix usually brighter and contain fewer impurities than their semi-precious cousins. Mineral: Minerals are the building blocks of the universe. Most rocks are made up of minerals. Each mineral has a clearly, scientifically defined chemical content and the atoms are put together, arranged, in a very specific way.  garnet (gem) MOHS Scale of Hardness MOHS Scale of Hardness 1. Talc 2. Gypsum The MOHS Scale of Hardness is a quick and 3. Calcite easy guide to help you figure out how hard a 4. Flourite rock is and it also aids you in identifying the 5. Apatite (turquoise, lapis lazuli) rock. The softest stone is Talc at number 1, 6. Orthoclase feldspar (epidote, with diamond being the hardest at number labradorite) 10. 7. Quartz (amethyst, aventurine) 8. Topaz (spinel, zirconia) Harder minerals (higher numbers on the 9. Corundum (ruby, sapphire) scale) will scratch softer ones (the ones with 10. Diamond smaller numbers). i.e. quartz will scratch orthoclase, apatite, fluorite, calcite, gypsum Quickie MOHS and talc, but it will not scratch topaz, 2.5 = fingernail 5.5 = pocket knife corundum or diamond! 3.5 = penny 6.5 = steel file
  • 5. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 5 This is a great book STEP 2: KNOW YOUR PLACE that was written by a local geologist. With Learn about the area in which you live, or this knowledge in places you can easily visit. Usually it’s hand, combined with possible to find a rockhound group, information on what lapidary or mineral society. They are formations are likely wonderful sources of information. to contain specific stones, my rock hunts Government websites also have are usually information on the geography and successful. geology of most regions. It’s easy to download maps or brochures that detail what kinds of minerals and rocks may be nearby. Take a class in geography, geology or rockhounding. Not only will you meet people with similar interests, but you may also learn of some new collecting sites! STEP 3: MIND YOUR MANNERS Whenever you are out looking for rocks, Map of world showing the distribution of major deposits plotted on digital have a rockhounding buddy with you and elevation model with draped geology from Geological Survey of Canada, make sure others know where you are Open File 2915d, 1995.Data from the synthesis of ore deposits. Data plotted and diagrams prepared by W.D. Goodfellow. going and approximately when you will return. Always get permission before entering private land. When in doubt, check with local authorities. Be careful. Take a first aid kit and know the local numbers for emergency assistance. Avoid active slide areas – no matter how great the “find”! Remember that caves can be dangerous –only enter with a trained spelunker. Know the type of rocks and minerals you will encounter beforehand. You want to avoid handling dangerous rocks and minerals. Galena (grey and very heavy) and sulfur (usually BRIGHT yellow) should The Skeen River, Terrace, British Columbia, Canada only be handled with gloved hands. Finally, leave the places you rockhound as you found them. Pick up litter and debris; fill holes, respect landowners and others who use the area.
  • 6. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 6 4. WHERE IN THE MOHS IS IT? By placing a rock within the MOHS scale, you are able to estimate the hardness of that rock. This can be helpful in identifying a stone. When testing for MOHS, you don’t need to scratch with all of your strength. Using normal pressure, like what you use when you are writing with a pencil, scrape the testing stone or tool across your rock. zircon Repeat this until your stone is scratched. If your stone is special, don’t use these tests, or do them in an area you won’t notice. 5. LOOKS DO COUNT Colour is extremely important in the identification of many rocks. Once you have seen the green of malachite you will always remember it. The appearance, or luster, of rocks is also helpful in their identification. Some will look some will look dull like chalk (slate has a “chalk” dullness), glassy – like a drinking Fibrous malachite glass (think of quartz or obsidian); greasy (graphite has a greasy feel); silky like silk (asbestos types look silky). 6. IT AIN’T HEAVY IT’S JUST TALC When you look in rock identification books, they usually provide the specific gravity (SG) of a rock or mineral. This is basically a comparison of the mineral or rock compared to the weight of an equal volume of water. Water has a SG of 1. The mineral sample above is “galena”. This is a Rocks that seem heavy for their size usually toxic mineral you should avoid handling with have a high density. The density of a stone bare hands. It, and lead, are noticeably generally refers to how tightly packed the “heavier” than most rocks. crystals are. i.e. Galena has an SG of~7.4- 7.6 and is quite dense, whereas sulfur weighs in at ~2-2.1 and isn’t nearly as dense as the galena.
  • 7. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 7 Common Streak Colours 7. STREAKING IS ALLOWED Limonite = Yellow-brown When it comes to rock & mineral identification Hematite = Red-brown – streaking is allowed! In fact, it is Gold = yellow encouraged! This is where the ceramic streak Galena = grey plates in your kit will come in handy. Graphite = black Pyrite = black To find out what colour streak your rock has, Magnetite = black you will scratch it across both plates – the Chalcopyrite = black white and the black unglazed ceramic. Sometimes you’ll be surprised, as the streak Below are a couple of examples where knowing left by a stone may be completely different the streak colour of stones can be quite useful. than the colour of its actual physical appearance! Minerals harder than the plate The colour streak for gold is yellow and Fool’s will not leave a streak. Gold (Pyrite) has a red streak! It is important to note that most silicates Hematite (a popular jewelry making stone) has (most of the stones we use in jewelry fall into a read streak, while galena (a toxic stone with the silicate class) have a white streak and this similar outward features) has a grey streak. may not help identify them. 8. POP, POP, FIZZ, FIZZ Next we will play with the vinegar and the nail. This tiny experiment can help you find out if there is calcite (calcium carbonate) present in your rock. Calcite is one of the most common minerals on earth - ~4% of the earth’s crust (by weight). Holding your rock firmly in your hand, scratch the surface with either a pocket knife or the nail in your ID kit. If you can’t scratch up a little bit of “shavings”, you definitely don’t have a rock that contains calcite. Now, drop one drop of vinegar onto the pile of “shavings”. If it fizzes, calcite is present. If it doesn’t, you probably don’t have calcite in your rock. Some folks use Muriatic (hydrochloric) acid in 10% dilution for this test. Because Muriatic acid can be extremely dangerous to handle, Rocks that contain calcium carbonate: it’s not something I suggest. Handling  Calcite (it IS calcium carbonate!) Muriatic acid requires special training and  Limestone hazard containment procedures.  Marble (it is compressed limestone)  Carbonatite Calcite can be the “glue” in:  Mexican Onyx  Sandstone  Iceland Spar  Slate
  • 8. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 8 THANK YOU! I hope this tutorial will help you identify some of the basic stones in your world. Remember, even experts have times when they can’t identify a rock specimen and need have it examined under a special microscope or have a chemical analysis. The best way to learn about The rock above is the one we’ll identify in this tutorial. rocks is to meet with other enthusiasts and explore as 9. WHAT IS IT? many different stones as Take out your first rock and give it a good look- possible. One of the best over. You might already have a good idea if you ways I learn about stones is are using a rockhound guide or map of deposits. through The Mineral of the Month Club. Can you tell if it is Igneous, Sedimentary or Metamorphic? I wish you a future filled My sample at left is Igneous – it looks with fascinating and like it cooled quickly because I don’t see beautiful rocks and any specific crystal formations. minerals! In my humble opinion, even a plain old basalt river rock is What kind of fracture or cleavage does it have? gorgeous enough to be used in making jewelry; The “fractures” are conchoidal. With my in fact it is one of my favourites! jeweler’s loupe I can see little “dishes” or bowl shapes. Where in the MOHS is this rock? Now we’ll use the MOHS scale to test my rock. Will #1 on the MOHS scale scratch it? No In fact, this stone isn’t scratched until we get to #8 on the MOHS scale. I tested it with zircon and it does scratch my stone. I also dragged my stone across the glass plate, just a little pressure is necessary. It scratched the plate. Now I know my stone is softer than #9. For comments or I tried scratching it with my nail and couldn’t get questions, please go to any “shavings”. JewelryLessons.com This tells me two things: 1. I don’t have calcium carbonate present in my rock and my rock is harder than the knife so Please do not distribute the MOH is greater than~5.5. or copy. I know by observation that my stone is pink in Copyrights 2008, Shelby Raymond, Skeena Storm appearance, as well as translucent and glassy. I Stones, http://skeenastormstones.com also know that the area is known for quartz; specifically rose quartz is frequently found. I All photos contained within this tutorial are the looked in my mineral book and sure enough, exclusive property of Shelby Raymond. everything matches up to rose quartz. With all of the information I now have, I Map photo on page 5 is the property of the know that my stone is rose quartz. Government of Canada.
  • 9. Identify that Rock – Updated 12-01-09 Copyright 2008 Shelby Raymond, Skeena Storm Stones Page: 9 SUGGESTED REFERENCES  A Field Guide to the Identification of Pebbles. Eileen Van der Flier-Keller. Harbour Publishing.2006. ISBN-10:1-55017-395-2 (This is an AWESOME little reference for identifying river rocks and “regular” stones!)  Rocks & Minerals. DK Publishing.2003. ISBN-13: 978-0-7894-9587-7  Guide to Minerals, Rocks & Fossils. A.C. Bishop, A.R. Woolley, W.R. Hamilton. Firefly Books. ISBN: 1-55407-054-6  National Audobon Society - First Field Guide: Rocks and Minerals. Edward Ricciuti, Margaret W. Carruthers. Scholastic Inc. 1998. ISBN: 0-590-0584-8  Mineral of the Month Club. http://mineralofthemonthclub.org (Please tell them Shelby Raymond referred you! Thanks.)  The Mineral and Locality Database. http://mindat.org  The Practical Geologist: The introductory guide to the basics of geology and to collecting and identifying rocks. Dougal Dixon. Raymond L. Bernor, Editor. Simon and Schuster, Fireside. 1992. ISBN-13: 978-0-671-74697-1  Amethyst Galleries' Mineral Gallery, http://mineral.galleries.com/  CANADA ROCKS: The Geologic Journey. Nick Eyles, Andrew Miall. Fitzhenry & Whiteside. 2007. ISBN: 978-1-55041-860-6  The Practical Geologist. Dougal Dixon. Raymond L. Bernor, Editor. 1992. Simon and Schuster/Fireside. ISBN: 978-0-671-74697-1 Disclaimer: Caution is urged while working with rocks and minerals. Children should always be supervised by a responsible adult. Shelby Raymond and Skeena Storm Stones are not liable for accidents, injuries or losses that may be incurred by use of this tutorial.