Man Made Byproduct (Often Mistaken For Obsidian Or Emerald)

Tiffany Stone

Bertrandite (with Fluorite, Opal, and Chalcedony), Be4Si2O7(OH)2

Obsidian

Obsidian (Extrusive Volcanic Glass)

Jade (likely Jadeite or Nephrite)

Jadeite (NaAlSi2O6) or Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Dendritic Agate (Tumbled)

Silicon Dioxide (SiO2) with inclusions

Quartzite

Quartzite (primarily SiO2)

Black tourmaline (likely schorl), polished

Schorl tourmaline — NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Quartzite

Quartzite (SiO2)

Chrysoprase

SiO2

Anthracite Coal with Sulfur staining

Anthracite (Carbon C with impurities)

Leland Blue Stone

Anthropogenic Iron Smelting Slag

Chert (varieties: Flint or Jasper)

Silicon dioxide (SiO2) / Microcrystalline Quartz

Tumbled black stone, likely obsidian

Obsidian — volcanic glass, chiefly silica-rich rhyolitic composition

Orange Calcite

Calcium Carbonate (CaCO3)

Bismuth

Bismuth (element Bi) with oxidized thin-film interference layer

Polished dark stone, possibly obsidian

Unidentified polished specimen; possibly volcanic glass (obsidian, silica-rich natural glass)

Quartzite

Quartzite (SiO2)

Emerald

Beryl (variety Emerald), Be3Al2Si6O18 with Cr and/or V

Diamond (Cluster Ring)

Carbon (C)

Silver (Sterling Silver Jewelry)

Argentum (Ag) mixed with Copper (Cu)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Black-and-white agate geode pendant

Agate (microcrystalline quartz, SiO₂), likely a hollow geode slice with chalcedony and drusy quartz

Green beryl (likely heliodor)

Beryl, Be₃Al₂Si₆O₁₈; yellow-green varieties are heliodor or golden beryl

Swirled Agate Bead

Silicon Dioxide (SiO2)

Diamond

Native Carbon (C)

Emerald in Matrix

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Schist

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

Emerald

Beryl (Be₃Al₂Si₆O₁₈), specifically the green variety colored by trace amounts of chromium or vanadium.

Green Quartz (Prasiolite or Aventurine)

Silicon Dioxide (SiO2)

Polished black stone, possibly basalt or black jasper

Basalt (fine-grained mafic rock) or microcrystalline quartz if jasper

Quartzite

Quartzite (SiO2)

Sea Glass

Silicon dioxide (mostly)

Pyrite

Iron Sulfide (FeS2)

Diamond

Carbon (C)

Chert

Microcrystalline Quartz (SiO2)

Flint

Silicon Dioxide (SiO2) - Chert variety

Pyrite-bearing rock (likely pyrite in a dark host rock)

Pyrite, FeS₂, with an unidentified host matrix

Quartzite

Quartzite (SiO2)

Greenstone

Greenschist (composed of actinolite, chlorite, and epidote)

Raw Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Green Fluorite

Calcium Fluoride (CaF2)

Chert (Chocolate or Brown Flint)

Chert (SiO2)