Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Category
Browse mineral (man made glass) specimens identified by the Rock Identifier community.
Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Garnet Beads
Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
White Jade (Nephrite)
Nephrite, Ca2(Mg,Fe)5Si8O22(OH)2
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Asphalt
Asphalt concrete (engineered material, not a naturally occurring rock/mineral in this form)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(F,OH)2)
Granite
Granite (a common rock name, not a single mineral species, composed primarily of quartz, feldspar, and mica/amphibole)
Gold (Elemental Metal)
Gold (Au)
Snowflake Obsidian
Spherulitic Obsidian (Amorphous volcanic glass with Phenocrysts of Cristobalite)
Green Fluorite (likely synthetic or heat-treated for jewelry)
Calcium Fluoride (CaF2)
Snowflake Obsidian
Volcanic Glass (SiO2 + impurities)
Lapis Lazuli
A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).
Crushed Limestone
Calcium Carbonate (CaCO3)
Muscovite Schist
Mica Schist (primarily KAl2(AlSi3O10)(OH)2)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Muscovite Mica (Golden/Yellow variety)
KAl2(AlSi3O10)(F,OH)2
Muscovite Mica
Muscovite: KAl2(AlSi3O10)(OH)2
Quartz (Variety of Rough Mineral Specimens)
Silicon Dioxide (SiO2)
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)
Quartz with Muscovite Mica
SiO2 with KAl2(AlSi3O10)(OH)2
Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
Borosilicate Glass (Manufactured)
SiO2 + B2O3 (Silicon dioxide and Boron trioxide)
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
Quartz
Quartz (SiO₂)
Citrine or Yellow Quartz
Silicon Dioxide (SiO2) with iron impurities
Muscovite Mica
Muscovite - KAl2(AlSi3O10)(OH)2
Sea Glass (Frosted Quartz/Glass)
Amorphous Silicon Dioxide (SiO2)
Obsidian
Volcanic glass (Mainly SiO2)
Slag Glass (Cullet Glass)
Amorphous Silica (Industrial byproduct)
Chert (or possibly Flint)
Chert (variant: Flint)
Mica (Muscovite)
Muscovite (KAl2(AlSi3O10)(OH)2)
Muscovite Mica in Quartz Matrix
Muscovite (KAl2(AlSi3O10)(OH)2) in Quartz (SiO2)
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (mostly SiO2)
Obsidian
Obsidian (principally SiO2 - Silicon Dioxide)