Mineral

Celestine (or Celestite)

Strontium sulfate (SrSO4)

Milky Quartz

Silicon Dioxide (SiO2)

Amethyst

Silicon dioxide with iron impurities (SiO2)

Larimar

Blue Pectolite (NaCa2Si3O8(OH))

Citrine

Silicon Dioxide (SiO2) with iron impurities

Tree Agate

Silicon Dioxide (SiO2) with Dendritic Inclusions

Rhodonite

Rhodonite (Manganese silicate, (Mn,Fe,Mg,Ca)SiO3)

Amethyst (Faceted)

Silicon Dioxide with Iron impurities (SiO2)

Smoky Quartz

Quartz (Silicon Dioxide) - SiO2

Rose Quartz

SiO2 (Silicon Dioxide with trace amounts of titanium, iron, or manganese)

Raw Emerald

Beryl (Be3Al2(SiO3)6) with Cr/V impurities

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Labradorite

(Ca, Na)(Al, Si)4O8 (Plagioclase Feldspar)

Rhodonite

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

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Chalcedony (Quartz Var.)

Silicon Dioxide (SiO2)

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)

Quartz Geode in Sedimentary Matrix

Silicon Dioxide (SiO2) within a limestone/dolostone host

Amazonite

Microcline (KAlSi3O8)

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Amethyst

Silicon Dioxide with Iron impurities (SiO2)

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)

Asphalt (Bituminous pavement fragment)

Artificial conglomerate / Bitumen-Aggregate mixture

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Garnet (Almandine/Pyrope variety)

Silicate mineral group; typically Fe3Al2(SiO4)3 (Almandine) or Mg3Al2(SiO4)3 (Pyrope)

Peridot (likely, based on color and appearance)

Olivine group mineral, specifically (Mg,Fe)2SiO4 (Forsterite-Fayalite solid solution series)

Sugilite

Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)

Garnet (likely Almandine or Pyrope)

Garnet Group (e.g., Almandine: Fe3Al2(SiO4)3; Pyrope: Mg3Al2(SiO4)3)

Mica Schist

Crystalline Schist (often containing Muscovite, Biotite, and Quartz)

Diamond (Uncut Crystal)

Carbon (C)

Quartz (Milky/Bull Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Geode (unopened)

Chert / Chalcedony Geode (SiO2)

Coarse-grained Quartz with Feldspar inclusions

Crystalline Quartz (SiO2) with Orthoclase/Plagioclase Feldspar inclusions

Foliated Gneiss (River-Worn Pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt

Pink Granite

Phaneritic intrusive igneous rock (Felsic)

Quartzite (Yellow/Iron-stained Quartz)

Quartzite (primarily SiO2 with iron oxide impurities)

Basalt with Quartz/Calcite Inclusions

Mafic Volcanic Rock (Fe-Mg silicate rich)

Granite with Orthoclase and Hematite Staining

Phaneritic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)

Quartzite Pebble (with Iron Inclusions)

Quartzite (primarily SiO2 with Fe2O3/FeOOH impurities)