Industrial Byproduct (Often Mistaken For Obsidian Or Mineral)

Amethyst

Quartz (Silicon Dioxide) with Ferric Iron impurities - SiO2

Rose Quartz

Silicon Dioxide with traces of Titanium, Iron, or Manganese (SiO2)

Rose Quartz

Silicon dioxide (SiO2) with trace impurities of titanium, iron, or manganese

Shale with Pyrite

Clastic sedimentary rock containing Iron Disulfide (FeS2)

Yellow Ochre / Limonite

Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)

Rough Emerald

Beryl (Be3Al2(SiO3)6 with Chromium/Vanadium impurities)

Sandstone Geode (Ironstone Concretion)

Arenite with Limonite/Hematite matrix (SiO2 with Fe-oxides)

Rutile in Quartz (Rutilated Quartz)

SiO2 with TiO2 inclusions

Red Sandstone (Iron-rich)

Ferruginous Sandstone (SiO2 with Iron Oxides)

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Chrysocolla

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)

Native Copper

Native Copper (Cu)

Moqui Marble (Concretion)

Iron Oxide Concretion (Hematite/Goethite)

Rhodonite

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

Native Copper

Native Copper (Cu)

Diamond (in a jewelry setting)

Cubic Carbon (C)

Limonite Concretion (Ironstone)

Limonite (Hydrated Iron(III) Oxide-Hydroxide, FeO(OH)·nH2O)

Blue Moss Agate / Blue Chalcedony

Silicon Dioxide (SiO2)

Oyster Shell (Aragonite/Calcite)

Calcium Carbonate (CaCO3)

Chert

Chert (Microcrystalline Quartz, SiO2)

Onyx Marble (also commonly called Onyx)

Calcite (CaCO3), often with other mineral impurities

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Greenschist / Chloritaform Schist

Chlorite Schist (Group of Silicate Minerals)

Turquoise

Hydrated phosphate of copper and aluminium - CuAl6(PO4)4(OH)8·4H2O

Limonite (vibrant yellowish-brown iron oxide)

Limonite (FeO(OH)·nH2O)

Blue Dyed Agate

Chalcedony (cryptocrystalline variety of Quartz), SiO2

Quartz (Gravel Pebble)

Silicon Dioxide (SiO2)

Chrysocolla and Malachite Beads

Hydrated copper silicates (Chrysocolla) and Copper carbonate hydroxide (Malachite)

Sandstone Concretion (Omar or Nut Rock)

Sedimentary Concretion (specifically an 'Omarolluk' or Omar)

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Milky Quartz with Iron Inclusions

Quartz (Silicon Dioxide, SiO2)

Fuchsite

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

Diopside (likely Chromian Diopside)

Diopside, part of Clinopyroxene family of inosilicates. Chemical formula: CaMgSi2O6. The green variety is often Chromian Diopside due to chromium impurities.

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Copper Ore

Native Copper (Cu) often found with Chalcocite (Cu2S) or Bornite (Cu5FeS4)

Calcite (Optical or Clear Calcite)

Calcium Carbonate (CaCO3)

Selenite (Satin Spar)

Gypsum (CaSO4·2H2O)

Chrysocolla (with Quartz and Azurite)

Hydrated copper phyllosilicate mineral [Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)]

Blue Calcite

Calcium Carbonate (CaCO3)

Leopard Skin Jasper

Silicon Dioxide (SiO2) with impurities

Hematite

Iron(III) oxide (Fe2O3)