Schist
N/A (a rock type, not a mineral formula)
metamorphic
Category
Anthropogenic Material (Man Made Sedimentary Mimic)
Browse anthropogenic material (man made sedimentary mimic) specimens identified by the Rock Identifier community.
Cinnabar in Quartz
Silicon Dioxide (SiO2) with Mercury Sulfide (HgS) inclusions
Mineral
Diamond in Kimberlite
Diamond in Kimberlite Matrix (Diamond: C, Kimberlite: complex Potassic Peridotite)
igneous
Diamond (in a jewelry setting)
Cubic Carbon (C)
mineral
Basalt with Mineral Vein (Cobble)
Basalt (with likely Quartz/Calcite vein)
Igneous
Fancy Jasper
Chalcedony (cryptocrystalline quartz) with inclusions
Mineral
Basalt
Basalt (Mafic volcanic rock)
igneous
White Jade / White Chalcedony
Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)
Mineral
Sandstone (likely Greywacke variant)
Arenite
sedimentary
Scoria
Scoria (a vesicular basalt or andesite)
igneous
Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Metamorphic Rock
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Pearl
Aragonite (CaCO3 with conchiolin)
mineral
Red Sandstone (Iron-rich)
Ferruginous Sandstone (variable formula, primarily SiO2 + Fe2O3)
sedimentary
Prase Quartz on Feldspar
Quartz (Silicon Dioxide, SiO2) with Hedenbergite inclusions on Potassium Feldspar (KAlSi3O8)
mineral
Diamond (Cluster Ring)
Carbon (C)
mineral
Chalcedony Geode
Chalcedony (SiO2) within a geode structure
Mineral Geode/Sedimentary or Volcanic related
Red Coral
Corallium rubrum (for precious red coral), although other species like Corallium japonicum and Paracorallium are also used.
Organic Gemstone (not a rock or mineral in the traditional sense, but bio-mineralized material)
Diamond in Kimberlite
Diamond (C in Kimberlite Matrix)
igneous
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
mineral
Rough Diamond
Diamond (pure Carbon, C)
mineral
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
igneous
Milky Quartz
Quartz (SiO2)
Mineral
Quartz
Silicon Dioxide (SiO₂)
Mineral
Quartz
Silicon Dioxide (SiO2)
Mineral
Quartz (Rock Crystal)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Pearl (with Peridot)
Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4
mineral
Schist
Schist (various mineral compositions)
Metamorphic
Rough Diamond
Diamond (pure Carbon, C)
mineral
Picture Jasper
Silicified sedimentary or volcanic rock (primarily SiO2)
sedimentary
Pearl
Aragonite (CaCO3) with Conchiolin
mineral
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
sedimentary
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
mineral
Quartzite
Quartzite (SiO2)
metamorphic
Agate (or Banded Agate)
Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)
Mineral, specifically a Cryptocrystalline Quartz variety
Fossilized Bone Fragment
Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)
sedimentary
Granodiorite with Quartz Veining
Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins
igneous
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Lazulite
Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Diamond (or Diamond Simulant)
Carbon (C)
mineral
Green Slag Glass
Amorphous Silica / Glassy Blast Furnace Slag
Mineraloid (Industrial byproduct)