Antropogenic (Man Made Glass Byproduct)

Chert

Microcrystalline Quartz (SiO2)

Green glassy cabochon, likely dyed or synthetic material

Uncertain; possibly green obsidian, chrysoprase, or synthetic glass

Granite (Pegmatitic)

Phaneritic Felsic Igneous Rock

Quartz (Crystal/Druzy Quartz)

Quartz (SiO₂)

Chert (specifically White Chert or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Dumortierite in Quartz

Dumortierite (Al6O3(BO3)(SiO4)3) with Quartz (SiO2)

Diamond

Carbon (C)

Iron-stained milky quartz

Quartz (SiO₂), mainly massive or vein quartz, with reddish-brown iron-oxide staining and possible minor feldspar or other vein minerals

Brown Jasper / River Siltstone

Silicon Dioxide (SiO2) with iron oxide impurities

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Rounded pebble, likely quartz-rich sandstone or chert

Indeterminate lithic clast; possibly quartz arenite or microcrystalline quartz (SiO₂)

Diamond

Carbon (C)

Mixed river-worn rock and mineral collection

Mostly quartz/quartzite, feldspar-bearing granitoid, chert, and mafic volcanic rocks; exact species vary by pebble

Pallasite Meteorite

Pallasite (Stony-Iron Meteorite)

Pearl (with Peridot)

Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4

Schist

N/A (a rock type, not a mineral formula)

Sandstone

Sedimentary Rock (Quartz Sandstone)

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Diamond (Faceted)

Carbon (C)

Raw Diamond

Carbon (C)

Diamond (in jewelry setting)

Adamantine Carbon (C)

Gneiss

Gneiss (a rock type, not a specific mineral with a formula)

Likely polished leopard-skin jasper or brecciated jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image alone

Pyrite

Iron Sulfide (FeS2)

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Diamond

C (Native Carbon)

Diamond

Natural Diamond (Carbon, C)

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Quartzite

Quartzite (SiO2)

Crazy Lace Agate

Chalcedony (Silicon Dioxide, SiO2)

Quartz Geode/Cluster

Quartz (SiO2)

Granite

Granite (a common term for a felsic intrusive igneous rock)

Sandstone

Arenite

Swirled Agate Bead

Silicon Dioxide (SiO2)

Sandstone

Arenite (general term for sandstone)

White seed-bead gemstone strand, likely freshwater pearl or shell pearl

Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image

Diamond (Cut Gemstone)

Natural Carbon (C)

Diamond (as set in a metal alloy ring)

Diamond (Pure Carbon, C)

Orthoclase Feldspar (or K-Feldspar)

Orthoclase (KAlSi3O8)

Quartz Geode/Druzy Quartz

Quartz (SiO₂)

Quartz (likely milky/gray variety)

Quartz (SiO₂)

Rhodonite beads (possibly dyed or treated, or lower quality Rhodonite)

Manganese inosilicate, (Mn,Fe,Mg,Ca)SiO3