Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Category
Mineral (Synthetic Paper And Ink Polymorph)
Browse mineral (synthetic paper and ink polymorph) specimens identified by the Rock Identifier community.
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Grey Basalt or Andesite with Veining
Intermediate to Mafic Extrusive Igneous Rock with Quartz/Calcite Veins
igneous
Granite
Intrusive Igneous Rock
igneous
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Orthoclase Feldspar with Quartz
Orthoclase (KAlSi3O8)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O)
mineral
Granite
Felsic intrusive igneous rock
igneous
Pearl
Calcium carbonate (CaCO3) + organic conchiolin
gemstone
Serpentine
Antigorite/Lizardite/Chrysotile group, Mg3Si2O5(OH)4
metamorphic
Hematite
Iron(III) oxide (Fe2O3)
mineral
Sedimentary Rock Fragments
Clastic Sedimentary Rock
sedimentary
Variscite (or potentially a turquoise/variscite matrix cabochon, or an impression jasper)
AlPO4·2H2O (Variscite) or related phosphate/silicate material depending on exact composition
Mineral
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Polished Agate (Yellow/Grey Agate Pendant)
Silicon Dioxide (SiO2)
mineral
Gypsum (Alabaster variety)
Calcium sulfate dihydrate (CaSO4·2H2O)
mineral
Granite
Intrusive Igneous Rock
igneous
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Pink Sapphire
Corundum (Al2O3 with chromium and iron traces)
gemstone
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (SiO2)
mineral
Milky Quartz
Silicon dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Bismuth Crystal
Bismuth (Bi)
mineral
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Potassium Feldspar and Quartz
KAlSi3O8 (Potassium Feldspar) and SiO2 (Quartz)
mineral
Botryoidal Chalcedony / Quartz
Silicon Dioxide (SiO2)
mineral
Feldspar
Aluminosilicate (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Quartz crystal cluster in matrix
Silicon dioxide (SiO2)
mineral
Sandstone
Clastic Sedimentary Rock
sedimentary
Schist
Schist (Crystalline metamorphic rock)
metamorphic
Gravel or Crushed Stone
Fragmented Aggregate Stone
sedimentary or igneous fragment
Rutilated Quartz
Silicon Dioxide (SiO2) with inclusions of Titanium Dioxide (TiO2)
mineral
Educational Geologic Collection
Mixed Mineral and Rock Collection (Various compositions)
mineral