Olivine (Peridot)
Olivine Group (Mg,Fe)2SiO4
mineral
Category
Organic Gem Material (Botanical)
Browse organic gem material (botanical) specimens identified by the Rock Identifier community.
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Likely calcite-rich limestone
Calcite (CaCO₃), probably micritic or fossiliferous limestone
sedimentary
Rhodonite
Manganese Inosilicate (Mn,Fe,Mg,Ca)SiO3
mineral
Polished ruby-in-zoisite (anyolite), likely
Ruby-bearing zoisite: zoisite Ca₂Al₃(SiO₄)₃(OH), with corundum Al₂O₃ and commonly amphibole
metamorphic
Amethyst druzy cluster
Amethyst, purple quartz (SiO₂)
mineral
Quartz with chlorite inclusions
Quartz (SiO₂), likely containing green chlorite-group minerals
mineral
Quartz-rich pegmatite (likely tourmaline-bearing)
Granitic pegmatite; primarily quartz (SiO₂), with feldspar and dark tourmaline/biotite
igneous
Pink tourmaline crystal (likely polished or rough-cut)
Elbaite, Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃
gemstone
Quartz-rich pegmatite with dark mica or tourmaline
Granite pegmatite; chiefly SiO₂ quartz with feldspar and probable biotite/black tourmaline
igneous
Jasper / Agate with Petrified Wood Inclusion
SiO2
mineral
Shark Tooth Fossil
Chondrichthyes (shark) tooth
fossil
Tufa Rock and Tumbled Gemstones
Calcareous Tufa (Calcium Carbonate, CaCO3)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
Sedimentary/Mineral
Sandstone (with Moss)
Quartz Arenite / Sandstone
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Poppy Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Pyrite Geode
Iron Disulfide (FeS2)
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper variation)
Chert (Cryptocrystalline microcrystalline Silicon Dioxide, SiO2)
sedimentary
Faceted amber-colored gemstone, possibly citrine
Unidentified transparent gem; citrine is quartz (SiO₂), but the image alone cannot confirm the material
gemstone
Uncertain: likely hematite-stained quartzite or iron-rich metamorphic rock
Quartz-rich, iron-oxide-stained rock; exact identification requires testing
metamorphic
Petrified Wood / Fossilized Bone
Silicified / Mineralized Fossil (Silica SiO2)
fossil
Diamond
Carbon (C)
gemstone
Amber
Succinite (C10H16O)
mineraloid
Polished blue-green feldspar (likely amazonite)
Amazonite, green microcline feldspar (KAlSi₃O₈)
mineral
Tumbled labradorite
Labradorite, a calcium-rich plagioclase feldspar; approximately (Ca,Na)(Al,Si)₄O₈
mineral
Tumbled tiger’s eye
Tiger’s-eye quartz (SiO₂), chatoyant quartz with crocidolite pseudomorphs
gemstone
Chrysocolla-bearing copper ore
Chrysocolla, hydrated copper phyllosilicate (approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O), likely mixed with malachite and/or turquoise
mineral
Green beryl (likely emerald)
Beryl, Be₃Al₂Si₆O₁₈; green gem-quality beryl is called emerald when its color is caused mainly by chromium and/or vanadium.
gemstone
Likely tumbled or cut carnelian
Microcrystalline quartz (SiO₂), chalcedony variety colored by iron oxides
gemstone
Green fluorite rough specimen
Fluorite (calcium fluoride, CaF₂)
mineral
Weathered greenstone / altered rock fragment
Probable chlorite–epidote–actinolite-rich metavolcanic rock; exact identification requires testing
metamorphic
Chrysocolla-rich copper ore
Chrysocolla (hydrated copper aluminosilicate), likely with malachite and copper oxides
mineral
Jasper
Chalcedony (SiO2)
mineral
Agatized or Silicified Fossil/Coral, or Jasper
SiO2
sedimentary
Fossil Shark Tooth
Otodus sp. or Carcharocles sp. (likely fossilized Chondrichthyes)
fossil
Fossil Shell
Brachiopod or Mollusk fossil
fossil
Jasper
Silicon dioxide (Quartz variety), SiO2
sedimentary
Chert (or Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Chalcedony/Common Opal)
Microcrystalline Quartz (SiO2)
sedimentary
Jasper Agate
Silicon dioxide (SiO2)
mineral