Red Sandstone
Arenite (Ferruginous Sandstone)
Category
Browse mineral specimens identified by the Rock Identifier community.
Red Sandstone
Arenite (Ferruginous Sandstone)
Sandstone Concretion with Quartz Center
Sedimentary Clastic Rock (SiO2 matrix with Quartz core)
Lapis Lazuli
Na6Ca2(Al6Si6O24)(S,SO4,Cl)1-2 (primarily containing Lazurite with inclusions of Calcite and Pyrite)
Turquoise in Matrix
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Fluorite
Calcium Fluoride (CaF2)
Fluorite (Polished Point/Tower)
Calcium Fluoride (CaF2)
Calcite (Yellow/Orange variety - sometimes called Honey Calcite)
Calcite
Given the appearance, it's likely a fragment of an igneous or metamorphic rock composed of multiple minerals. Without specific diagnostic features, it's difficult to give a common name other than 'crystalline rock fragment'. If pressed to guess based on the granular, somewhat light and dark speckled appearance, it could be a fragment of granite or a related intrusive igneous rock.
As a rock fragment, it does not have a single scientific mineral name; rather, it's a piece of a rock which is a combination of minerals. If it were granite, its main mineral composition would be quartz (SiO2), feldspar (e.g., KAlSi3O8 - orthoclase, (Na,Ca)(Al,Si)4O8 - plagioclase), and mica (e.g., KAl2(AlSi3O10)(OH)2 - muscovite or K(Mg,Fe)3AlSi3O10(OH)2 - biotite), among others.
Schist with Biotite and Quartz
Biotite-Quartz Schist (Fe,Mg,Al silicate mix)
Lapis Lazuli (Raw)
Lazurite-rich metamorphic rock; Na3Ca(Al3Si3O12)S
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Fluorite (Rainbow/Purple Fluorite)
Calcium Fluoride (CaF2)
Malachite
Copper carbonate hydroxide [Cu2CO3(OH)2]
Fluorite (likely Fluorite on Quartz/Matrix)
Calcium Fluoride (CaF2)
Orthoclase Feldspar
Orthoclase (KAlSi₃O₈)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Bumblebee Jasper
Anhydrite with Sulfur, Hematite, and Orpiment (SiO2/CaSO4 mixture)
Lapis Lazuli
Lapis Lazuli (Rock composed primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)
Goethite/Limonite Iron Ore Node
Goethite (FeO(OH)) or Limonite (mixture of hydrated iron oxides)
Turquoise
Turquoise (CuAl6(PO4)4(OH)8·4H2O)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Turquoise with Pyrite
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O] with Iron Pyrite (FeS2)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
Dalmatian Stone
Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)
Magnetite
Magnetite (Fe3O4)
Mica Schist
Schist (primarily Muscovite and Biotite mica)
Sandstone (likely Arkosic)
Arenite (SiO2 based)
Chert with Calcite Veins
Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Sandstone (likely Arkose or Lithic)
Clastic sedimentary rock (SiO2 + impurities)
Chalcopyrite
Copper Iron Sulfide (CuFeS2)
Sandstone (Ferruginous)
Arenite with Iron Oxides
Granodiorite
Granodiorite
Gneiss (specifically a granitic gneiss cobble)
Gneiss (high-grade regional metamorphic rock)
Dyed Quartz (often sold as 'Blue Quartz' or 'Blue Agate')
Silicon Dioxide (SiO2) with artificial pigment
Granite
Granite (Felsic intrusive igneous rock)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Granitic Gneiss
Gneiss (Complex silicate composition)
Slate
Foliated Metamorphic Rock (primarily composed of quartz, illite, chlorite, and micas)