Man Made Byproduct (Often Mistaken For Obsidian Or Emerald)

Limestone

Calcium Carbonate (CaCO3)

Carved yellow stone butterfly

Undetermined; possibly carved soapstone (talc-rich rock) or another soft ornamental stone

Asphalt Concrete

Bituminous conglomerate

Obsidian

Obsidian (Volcanic Glass), primarily SiO2

Rough Emerald

Beryl (Be3Al2Si6O18 with Chromium and Vanadium impurities)

Blue crystal pendant (likely blue glass or synthetic crystal)

Not identifiable from the image; possibly synthetic quartz or glass, rather than a natural mineral

Obsidian

Obsidian (Volcanic Glass)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Obsidian

Obsidian (Volcanic Glass)

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Mixed Mineral Collection (with Quartz, Beryl, and host rock)

Silicon Dioxide (Quartz), Be3Al2Si6O18 (Beryl), and associated Schist/Pegmatite

Diamond (or Simulant)

Carbon (C)

Obsidian

Obsidian (Volcanic Glass)

Obsidian

Obsidian (Volcanic Glass)

Diamond (Cut Gemstone)

Carbon (C)

Sandstone

Arenite (mostly SiO2)

Rough Diamond

Diamond (Pure Carbon: C)

Emerald in Matrix (Tumbled)

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Fuchsite or Green Mica Schist

Muscovite variant (KAl2(AlSi3O10)(OH)2 with Cr)

Obsidian

Obsidian (Volcanic Glass)

Quartzite

Quartzite (SiO2)

Tumbled black obsidian

Obsidian (volcanic glass), primarily rhyolitic silica glass

Green cabochon gemstone, likely glass-filled or synthetic emerald imitation

Uncertain; possible synthetic emerald (beryl, Be₃Al₂Si₆O₁₈) or green glass

Obsidian

Obsidian (volcanic glass; primarily SiO2)

Emerald in Matrix

Beryl (Be3Al2Si6O18 with Chromium/Vanadium traces)

Dendritic Quartz

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Pearl

Calcium carbonate (CaCO3) - mainly Aragonite with Conchiolin

Green Fuchsite and Quartz

K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)

White drusy quartz

Quartz, silicon dioxide (SiO₂), with a drusy coating of tiny crystals

Obsidian

Obsidian (principally SiO2)

Obsidian

Volcanic Glass (predominantly SiO2)

Obsidian

Obsidian (Volcanic Glass)

Emerald in Matrix

Beryllium Aluminum Silicate (Be3Al2Si6O18) with Chromium/Vanadium impurities

Slag (Industrial Byproduct)

Anthropogenic Vitreous Silicate material

Peridot (Olivine)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Black obsidian

Volcanic glass, predominantly rhyolitic silica glass (approximately 70–80% SiO₂)

Fuchsite (Chrome Mica)

K(Al,Cr)2(AlSi3O10)(OH)2

Chert (often called Flint for darker varieties)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Obsidian

Volcanic Glass

Emerald (cut gemstone)

Beryl, Be₃Al₂Si₆O₁₈, colored green mainly by chromium and/or vanadium

Obsidian

Obsidian (Volcanic Glass)

Obsidian

Volcanic Glass (Amorphous SiO2)