Green Moonstone
Potassium Aluminum Silicate (KAlSi3O8)
Category
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Green Moonstone
Potassium Aluminum Silicate (KAlSi3O8)
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
Jasper
Jasper (Silica, SiO2)
Septarian Nodule
Septarian Concretion
Amber
Succinite (organic hydrocarbon)
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Pearl (likely Freshwater or Akoya Cultured)
Aragonite / Conchiolin composite (CaCO3)
Red Jasper
Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)
Lepidolite
K(Li,Al)3(Si,Al)4O10(F,OH)2
Carnelian (Red Chalcedony)
Silicon Dioxide (SiO2) - variety of Chalcedony
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)
Granite
Granite (a plutonic igneous rock composed primarily of quartz and feldspar)
Hematite
Iron(III) oxide (Fe2O3)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Slate
Phyllo-silicate based metamorphic rock
Jade (Nephrite and Jadeite)
Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2; Jadeite: NaAlSi2O6
Unakite
Epidotized Granite
Unakite
Epidotized Granite
Copper Ore (with Azurite and Malachite)
Cuprite, Azurite (Cu3(CO3)2(OH)2), Malachite (Cu2(CO3)(OH)2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si)4O10(F,OH)2)
Rhyolite
Rhyolite
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS)
Pyromorphite on Epidote
Pyromorphite [Pb5(PO4)3Cl] and Epidote [Ca2(Al2,Fe3+)(SiO4)3(OH)]
Blue Apatite
Apatite-(CaF), Ca5(PO4)3F
Red Jasper (Chert)
Silicon Dioxide (SiO2)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2 (Chromium-rich Muscovite)
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Granodiorite
Granodiorite (containing Quartz, Plagioclase Feldspar, Biotite, and Hornblende)
Chert (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Jasper
Silicon dioxide (SiO2)
Jasper (specifically Chert/Ironstone)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Cavansite
Cavansite (Ca(VO)Si4O10·4H2O)
Almandine Garnet
Iron aluminum silicate - Fe3Al2(SiO4)3
Garnet (Almandine variety)
Almandine Garnet (Fe3Al2(SiO4)3)
Chert (often referred to as 'Jasper' when red)
Chert (microcrystalline quartz, SiO₂)
Jasper
Chalcedony (cryptocrystalline quartz), SiO2
Garnet (likely Almandine)
Almandine Garnet, Fe3Al2(SiO4)3
Pearl
Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3
Chrysocolla on Limonite Matrix
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla) on FeO(OH)·nH2O (Limonite)
Chalcedony (Agate/Carnelian type)
Silicon Dioxide (SiO2)