Shale
Shale (Lutite)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Shale
Shale (Lutite)
Shale
Fissile mudstone (rich in clay minerals and quartz)
Pegmatite
Granitic Pegmatite
Peridot
Olivine ((Mg, Fe)2SiO4)
Sandstone
Arenite (primarily SiO2)
Shale
Fissile mudrock (composed of clay-sized particles and detrital grains)
Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities
Pyrite
Iron Sulfide (FeS2)
Halite (Rock Salt)
Halite (Sodium Chloride, NaCl)
Diamond
Diamond (pure Carbon, C)
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide impurities
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Sunstone
Oligoclase (Plagioclase Feldspar) - (Ca,Na)(Al,Si)4O8
Peach Moonstone
Orthoclase Feldspar (KAlSi3O8) with inclusions
Rhodonite Tumbled Chips
Manganese silicate (Mn,Fe,Mg,Ca)SiO3
Red Jasper
Silicon Dioxide (SiO₂)
Sunstone
Aventurine Feldspar (composition: (Ca,Na)((Al,Si)2Si2O8))
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate - (Mn,Fe,Mg,Ca)SiO3)
Turquoise in Matrix
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Peridot (Olivine)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Flesh-toned Siltstone
Siltstone (composed of microscopic Quartz and Feldspar grains)
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Chalcedony
Chalcedony (a microcrystalline variety of Quartz, SiO2)
Quartz
Quartz (SiO₂)
Emerald
Emerald (Beryl variety); Be3Al2(SiO3)6 with Chromium/Vanadium impurities
Apatite
Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))
Amethyst
Silicon Dioxide with Iron impurities (SiO2)
Unakite Pebble
Epidotized Granite
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Tiger's Eye
SiO2 (Silicon Dioxide with Iron Oxide inclusions)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe)
Larimar
Pectolite (Blue variety), NaCa2Si3O10(OH)
Milky Quartz
Silicon Dioxide (SiO2)
Nuummite
Nuummite (Ortho-amphibole rock, primarily Anthophyllite and Gedrite)