Quartz / Common Gravel
Silicon Dioxide (SiO2)
Category
Browse organic gemstone (not a rock or mineral in the traditional sense, but bio mineralized material) specimens identified by the Rock Identifier community.
Quartz / Common Gravel
Silicon Dioxide (SiO2)
Mica (Muscovite)
Muscovite (KAl2(AlSi3O10)(OH)2)
Blue Topaz
Aluminum Silicate Fluoride Hydroxide Al2SiO4(F,OH)2
Siltstone
Siltstone (primarily composed of SiO2 with various clay minerals)
Siltstone with iron staining
Siltstone (primarily SiO2 with FeO(OH) coatings)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Milky Quartz with Hematite/Limonite staining
Silicon Dioxide (SiO2)
Biotite (Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
Banded Agate
Agate (Cryptocrystalline variety of Silica, SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Diamond
Diamond (C)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Quartz with Muscovite Mica
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)
Schist
Mica Schist
Quartz (Small Pebble)
Silicon Dioxide (SiO2)
Slate
Slate
Chert (Iron-stained)
Chert (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Quartz (Small Pebble)
Silicon Dioxide (SiO2)
Pyrite-bearing Schist
Pyritic Quartz-Mica Schist with FeS2 inclusion
Pyrite
Iron Sulfide (FeS2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Dendritic Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
Pink Polished Marble (or Limestone) Pillar
Recrystallized Calcium Carbonate (CaCO3)
Malachite with Chrysocolla
Copper carbonate hydroxide (Cu2CO3(OH)2) and Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Iron-stained Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Banded Agate (specifically Carnelian Agate)
Cryptocrystalline Quartz (SiO2)
Sunstone
Oligoclase (Plagioclase Feldspar) - (Ca,Na)(Al,Si)4O8 with Hematite or Copper inclusions
Red Jasper with Fossils
Silicified Fossiliferous Jasper (Chert variant, SiO2)
Fluorite
Calcium fluoride (CaF2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Quartz (small fragment)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Amazonite
Microcline (KAlSi3O8) with lead impurities
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Chalcedony (Agate/Carnelian variety)
Cryptocrystalline Quartz (SiO2)
Amber
Succinate (Fossilized Tree Resin)
Amber with Inclusion
Succiniferous fossil resin (C10H16O)
Rough Diamond
Diamond (pure carbon, C)
Hematite
Iron(III) oxide (Fe2O3)