Black Tourmaline in Quartz
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4) in Silicon Dioxide (SiO2)
Category
Browse organic mineral specimens identified by the Rock Identifier community.
Black Tourmaline in Quartz
Schorl (NaFe3Al6(BO3)3Si6O18(OH)4) in Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Gold Nugget
Native Gold (Au)
Tiger's Eye
Pseudomorph of quartz after crocidolite (SiO2 with iron oxide inclusions)
Citrine (likely Heat-Treated Amethyst)
Silicon Dioxide (SiO2)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
Granite
Granite (composed primarily of Quartz SiO2, Feldspar KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8, and Mica)
Howlite and Purpurite druzy
Calcium Borosilicate Hydroxide (Howlite) and Manganese Phosphate (Purpurite)
Tumbled Moonstone
Feldspar (Orthoclase/Albite), KAlSi3O8
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Quartz Geode
Silicon Dioxide (SiO2)
Satin Spar (often sold as Selenite)
Gypsum (CaSO4·2H2O)
Sandstone
Arenite (SiO2 primarily)
Granite
Phaneritic Igneous Rock (Granite)
Green Aventurine
Quartz with Fuchsine inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Chrysocolla
Chrysocolla, (Cu, Al)2H2Si2O5(OH)4·nH2O
Corundum
Corundum (Aluminium oxide, Al2O3)
Granite Cobble
Granite
Basalt with Quartz/Feldspar Vein
Amygdaloidal Basalt with Plutonic intrusion (SiO2/KAlSi3O8)
Granite
Granite (Felsic intrusive igneous rock)
Charoite
Charoite (Hydrated potassium, sodium, calcium, barium, strontium silicate hydroxide fluoride)
River Stone (Granitic Gneiss)
Foliated Granitic Gneiss
Gneiss
Gneiss
Copper-bearing Quartz (likely Malachite on Quartz matrix)
Cu2CO3(OH)2 (Malachite) on SiO2 (Quartz)
Greenstone
Metabasalt / Greenschist facies rock
Granite Pebble
Granite (Phaneritic intrusive igneous rock)
Granite (Pink/Red)
Phaneritic Plutonic Felsic Rock (major minerals: Quartz, Orthoclase Feldspar, Plagioclase Feldspar)
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Granite
Plutonic felsic rock (Quartz, Feldspar, Mica)
Quartz Pebble (with probable inclusions or staining)
Quartz (Silicon Dioxide - SiO2)
Granite (with Orthoclase and Quartz)
Phaneritic Felsic Igneous Rock (KAlSi3O8 + SiO2)
Diorite (River Rock)
Intermediate plutonic igneous rock
Sandstone (Greywacke)
Arenite / Clastic Sedimentary Rock
Granite featuring Quartz Vein
Granite with hydrothermal silica (SiO2) intrusion
Diamond (Macled/Crystal fragment)
Carbon (C), isometric crystal system
Granite
Granite (Phaneritic igneous rock)
Milky Quartz with Pyrite inclusions
Silicon Dioxide (SiO2) with Iron Disulfide (FeS2)
Sandstone
Arenite (SiO2 based with various mineral cements)
Quartz Pebble
Silicon Dioxide (SiO2)
Basalt
Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Rough Diamond
Diamond (pure Carbon, C)
Diamond
Diamond (pure Carbon, C)