Amazonite
Potassium aluminum silicate (KAlSi3O8)
Category
Browse mineral (variety of chalcedony) specimens identified by the Rock Identifier community.
Amazonite
Potassium aluminum silicate (KAlSi3O8)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
Marble
Metamorphosed Limestone (calcite formulation CaCO3)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Yellow Jasper (Mookaite style)
Silicon Dioxide (SiO2) with Goethite/Hematite inclusions
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Calcite
Calcite (Mineral, Calcium Carbonate - CaCO3)
Chert (and Chalcedony/Agate mixture)
Microcrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Clastic Sedimentary Rock (Litharenite)
Pyrite
Iron Pyrite (FeS2)
Pink Granite
Granite (Phaneritic igneous rock rich in Alkali Feldspar and Quartz)
Dragon Blood Jasper
Epidote with Red Jasper inclusions (SiO2 and Ca2(Al,Fe)3(SiO4)3(OH))
African Turquoise (Jasper)
Polychrome African Jasper (often marketed as 'African Turquoise' due to its color, but it is not true turquoise)
Sandstone
Arenite (primarily SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Black Opal
Amorphous Hydrated Silica (SiO2·nH2O)
Watermelon Tourmaline
Elbaite - Na(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3OH
Milky Quartz
Silicon Dioxide (SiO2)
Schorl (Black Tourmaline)
Schorl (Sodium Iron Aluminum Borosilicate Hydroxide), NaFe3Al6(BO3)3Si6O18(OH)4
Satin Spar (often marketed as Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
Milky Quartz
Silicon Dioxide (SiO2)
Schorl (Black Tourmaline)
NaFe3Al6(BO3)3Si6O18(OH)4 (Complex Borosilicate)
Yellow Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Selenite (Gypsum Variety)
Hydrous Calcium Sulfate (CaSO4·2H2O)
Rough Corundum (likely Sapphire/Zircon-bearing)
Aluminium Oxide (Al2O3)
Quartz on Matrix
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese
Schist
Mica Schist (Variable chemistry, often rich in muscovite and biotite)
Rose Quartz
Quartz (Silicon Dioxide - SiO2)
Marble
Recrystallized Calcite (CaCO3) Rock
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Amethyst
SiO2 (Silicon Dioxide)
Smoky Quartz
Silicon Dioxide (SiO2)
Black Opal
Hydrated Silica (SiO2·nH2O)
Prase Quartz on Feldspar
Quartz (Silicon Dioxide, SiO2) with Hedenbergite inclusions on Potassium Feldspar (KAlSi3O8)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milk Quartz (Tumbled)
Silicon Dioxide (SiO2)