Specimen Desk
Rock & Mineral Identification
Tools and references for turning an interesting find into a defensible identification with clear notes.
Featured materials
Common member references
- Quartz Family Decision Tree
- Sedimentary Texture Quick Check
- Safe Scratch Testing Procedure
Identification workflow
Observe, test, compare, document uncertainty, and cite the ARE field guide used.
Lapidary context
Member notes explain hardness, fracture, polish response, and common lookalikes.
Digital specimen cards
Printable cards keep locality, date, collector, tests, and photos together.
In this section
Mohs
Amethyst Identification Sheet
The purple quartz that has captivated collectors and jewelers for millennia — and fades if you leave it on the windowsill.
Mohs
Azurite Identification Sheet
The deep azure-blue copper carbonate, malachite's constant companion, confirmed by its light blue streak and acid reaction.
Mohs
Beryl (Aquamarine and Emerald) Identification Sheet
The beryllium silicate behind emerald, aquamarine, and morganite: long hexagonal prisms, harder than quartz, in pegmatites.
Mohs
Calcite Identification Sheet
How to confirm calcite using hardness, cleavage, and the dilute-acid reaction test.
Mohs
Corundum (Ruby and Sapphire) Identification Sheet
The Mohs 9 anchor at the top of every field kit: ruby and sapphire are the same mineral, identified by extreme hardness and barrel-shaped…
Mohs
Feldspar Identification Sheet
The mineral that makes up 60% of the Earth's crust — and still trips up new collectors.
Mohs
Fluorite Identification Sheet
The mineral that gave fluorescence its name — and comes in nearly every color imaginable.
Mohs
Galena Identification Sheet
The primary lead ore: soft, very heavy, bright lead-grey metallic, with perfect cubic cleavage.
Mohs
Garnet Group Identification Sheet
Not one mineral but a family — hard, dense, and found in almost every metamorphic rock Rockies encounter.
Mohs
Halite (Rock Salt) Identification Sheet
Common rock salt: cubic crystals, perfect cubic cleavage, and the only identification sheet where the taste test is the approved test.
Mohs
Hematite Identification Sheet
The most important iron ore, identified by its diagnostic reddish-brown streak regardless of the specimen's outward color.
Mohs
Magnetite Identification Sheet
The strongly magnetic iron oxide: black streak, octahedral crystals, and a pull on the pocket magnet no lookalike can match.
Mohs
Malachite Identification Sheet
A bright green copper carbonate recognized by its color, concentric banding, botryoidal habit, and effervescence in acid.
Mohs
Muscovite Mica Identification Sheet
The sparkly sheet mineral in every granite — and the one that makes students understand cleavage for the first time.
Mohs
Obsidian Identification Sheet
Volcanic glass that looks like a mineral but technically isn't — and produces the sharpest natural edges known.
Mohs
Olivine (Peridot) Identification Sheet
The green mineral that makes up much of the Earth's mantle — and surfaces as gemstone peridot when conditions align.
Mohs
Onyx Identification Sheet
A banded chalcedony with a parallel-layered structure, a hardness that outlasts most imposters, and — in this particular library — a name…
Mohs
Pop Rocks (Pressurized Vesicular Sucrose) Identification Sheet
A vesicular carbonated sugar rock exhibiting spontaneous exothermic dissolution and audible degassing upon contact with moisture — first …
Mohs
Pyrite (Fool's Gold) Identification Sheet
How to tell pyrite from actual gold — and why every newcomer gets fooled at least once.
Mohs
Quartz Identification Sheet
Field identification cues for quartz and its common varieties, with a decision path for separating it from lookalikes.
Mohs
Rhodochrosite Identification Sheet
Colorado's rose-pink state mineral: a manganese carbonate identified by color, low hardness, rhombohedral cleavage, and a warm-acid react…
Mohs
Rock Candy (Sucrose Crystal) Identification Sheet
A monocrystalline or polycrystalline sucrose formation exhibiting exceptional optical clarity and notable solubility in aqueous environme…
Mohs
Selenite (Gypsum) Identification Sheet
A very soft sulfate you can scratch with a fingernail, forming clear bladed crystals, satin spar, and desert roses.
Mohs
Sphalerite Identification Sheet
The principal zinc ore and a notorious deceiver: brilliant adamantine to resinous luster, six-direction cleavage, and a pale streak that …
Mohs
Talc Identification Sheet
The Mohs 1 anchor at the bottom of the scale: so soft a fingernail scratches it, with a greasy, soapy feel no other common mineral shares.
Mohs
Topaz Identification Sheet
The Mohs 8 reference mineral: hard enough to scratch quartz, with perfect basal cleavage and striated prismatic crystals.
Mohs
Turquoise Identification Sheet
One of the world's oldest ornamental stones — and one of the most frequently faked.
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