Biotite Mica in Host Rock
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Category
Browse metamorphic (localized) or sedimentary specimens identified by the Rock Identifier community.
Biotite Mica in Host Rock
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Citrine (likely Heat-Treated)
Quartz (Silicon Dioxide, SiO2)
Native Gold (in the form of jewelry)
Gold (Au)
Smoky Quartz (with possible Garnet inclusions)
Silicon Dioxide (SiO2)
Breciated Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Muscovite Mica in Quartz Matrix
Muscovite (KAl2(AlSi3O10)(OH)2) in Quartz (SiO2)
Star Sapphire
Corundum (Al2O3) with Rutile inclusions
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Ruby (Corundum)
Al2O3 (Aluminium oxide with Chromium impurities)
Serpentinite
Serpentinite (composed primarily of minerals in the Serpentine group: Chrysotile, Lizardite, and Antigorite)
Muscovite (Mica) in Quartz Matrix
Muscovite (KAl2(AlSi3O10)(OH)2) and Quartz (SiO2)
Banded Agate
Cryptocrystalline Quartz (SiO2)
Blue Sapphire
Corundum (Al2O3)
Banded Agate (Pink/Peach Chalcedony)
Agate (Silicon Dioxide, SiO2)
Unakite
Epidotized Granite
Blue Sapphire
Corundum (Al2O3 with trace Titanium/Iron)
Arsenopyrite with Quartz
Arsenopyrite (FeAsS)
Sodalite
Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)
Rough Citrine Quartz
Silicon Dioxide (SiO2) with ferric iron impurities
Blue Sapphire
Corundum (Al2O3 - Aluminum Oxide)
White Quartz
Silicon Dioxide (SiO2)
Quartz (Iron-Stained or Milky Quartz)
Silicon Dioxide (SiO2)
Ruby
Corundum (Al2O3) with Chromium traces
Muscovite Mica (with Quartz matrix)
Muscovite - KAl2(AlSi3O10)(OH)2
Nuummite
Nuummite (Orthoamphibole rock composed of Anthophyllite and Gedrite, (Mg,Fe)7Si8O22(OH)2)
Moonstone (Feldspar)
Orthoclase (KAlSi3O8) or Albite (NaAlSi3O8)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Yellow Quartz (Citrine or Iron-Stained Quartz)
Silicon Dioxide (SiO2)
Orthoclase Feldspar
Potassium aluminum silicate (KAlSi3O8)
Red Garnet
Almandine and Pyrope (Silicate minerals: Fe3Al2(SiO4)3 and Mg3Al2(SiO4)3)
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Tiger's Eye
Pseudomorph of Crocidolite (SiO2 with iron oxides)
Green Aventurine
Aventurine Quartz (SiO2 with inclusions)
Banded Agate (Onyx Variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Serpentine
Serpentine (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4
Quartz (Engineered Stone Countertop)
Silicon Dioxide (SiO2) within a resin matrix
Staurolite (Cross Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
Quartzite Cobble
Quartzite (predominantly SiO2)
Quartzite Pebble
Metamorphosed Sandstone (mainly SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)