Organic Gemstone (Not A Mineral)

Amethyst Quartz

Amethyst (SiO2 with Iron impurities)

Amazonite

KAlSi3O8 (Potassium Aluminum Silicate) - a variety of Microcline Feldspar

Larimar

Pectolite (a variety of pectolite, NaCa2Si3O8(OH))

Diamond

Diamond (C)

Moonstone

Orthoclase Feldspar (specifically showing adularescence)

Amazonite

Amazonite (KAlSi3O8, a variety of Microcline)

Travertine (used in construction, not a 'specimen' in situ)

Travertine

Amethyst (Tumbled)

Silicon Dioxide (SiO2) with iron impurities

Diamond

Native Carbon (C)

Smoky Quartz

Smoky Quartz (SiO ₂)

Jasper

Jasper (Silicon Dioxide, SiO2 with iron inclusions)

Yellow Chalcedony (Agate)

Silicon Dioxide (SiO2)

Quartz (Microcrystalline/Chert)

Silicon Dioxide (SiO2)

Garnet (specifically Almandine or Pyrope)

Almandine (Fe3Al2Si3O12) or Pyrope (Mg3Al2Si3O12)

Rose Quartz

SiO2 (Silicon Dioxide)

Raw Diamond

Diamond (pure Carbon, C)

Amethyst

Silicon dioxide with iron impurities (SiO2 + Fe3+)

Diamond

Carbon (C)

Chert Pebble (Yellow Jasper)

Microcrystalline Quartz (SiO2)

Peridot and Citrine Gemstones (in a ring setting)

Peridot (Olivine: (Mg,Fe)2SiO4), Citrine (Quartz: SiO2)

Schist (Garnet-Mica Schist)

Garnet-Mica Schist (X-Y)3Z2(SiO4)3

Aquamarine

Beryl (Be₃Al₂Si₆O₁₈), specifically a blue or cyan variety

Chalcopyrite

Chalcopyrite (CuFeS2)

Green Aventurine

Quartz (SiO2) with Fuchsite inclusions

Jadeite

Jadeite (NaAlSi2O6)

Fluorite in Matrix

Fluorite (CaF2) within a host rock matrix

Yellow Apatite Sphere (Polished)

Fluorapatite / Ca5(PO4)3F

Ruby (set in a gold pendant)

Ruby (Variety of Corundum, Al2O3)

Amethyst

Quartz (Silicon Dioxide with iron impurities), SiO2

Labradorite (a variety of Feldspar)

Labradorite; (Na,Ca)(Al,Si)4O8 (a plagioclase feldspar)

Pegmatitic Granite

Granite with Orthoclase Feldspar and Quartz (SiO2, KAlSi3O8)

Diamond

Diamond (pure Carbon, C)

Chalcedony (Yellow Agate/Chert)

Silicon Dioxide (SiO2)

Diamond (set in jewelry)

Diamond (Carbon, C)

Diamond

Diamond (pure carbon, C)

Diamond

Diamond (pure Carbon, C)

Blue Sapphire

Corundum (Al2O3)

Basalt-Amugydule (Amygdaloidal Basalt)

Aphanitic Mafic Igneous Rock with Vesicle Infillings

Garnet-Bearing Schist

Almandine Garnet Micaceous Schist

Carnelian

Carnelian (Silicon Dioxide: SiO2)

Amethyst (Quartz variety)

Amethyst [Silicon Dioxide (SiO2)]

Carnelian (Chalcedony variety)

SiO2 (Silicon Dioxide)