Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Category
Browse mineral (man made composite) specimens identified by the Rock Identifier community.
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Chrysocolla Chalcedony
Hydrated Copper Phyllosilicate (Cu,Al)2H2Si2O5(OH)4 + SiO2
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
Kunzite
Spodumene (LiAlSi2O6)
Epidote with Magnetite/Hematite inclusions
Epidote (Ca2(Al2,Fe3+)(SiO4)3(OH)) with Iron Oxides
Sandstone
Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)
Mica Schist
Mica Schist (Main mineral constituents: Muscovite/Biotite, Quartz, Feldspar)
Veined Basalt River Stone
Basalt with Calcite or Quartz veining
Granite
Granite
Biotite (Mica)
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Gossan (Iron Hat) with Quartz and Chlorite
Limonite/Goethite-rich Gossan (FeO(OH)·nH2O) with inclusions of Quartz and Chlorite
Sandstone (Tumbled/River Pebble)
Arenite (composed primarily of SiO2)
Sandstone
Arenite (SiO2 based with primary clasts 0.0625 to 2 mm)
Malachite Coating on Host Rock
Malachite [Cu2CO3(OH)2]
Turquoise and Hematite
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)
Limonite/Goethite (Iron Ore)
Hydrous ferric oxides (FeO(OH)·nH2O)
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Malachite
Copper(II) carbonate hydroxide [Cu2CO3(OH)2]
Limonitic Iron Ore / Goethite
Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)
Quartz
Quartz (SiO₂)
Quartzite
Quartzite (primarily SiO2)
Mixed Crushed Stone
Aggregate (varied mineral composition)
Moqui Marble (Sandstone Concretion)
Hematite-cemented Sandstone (Fe2O3 + SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Granite Gneiss
Granitic Gneiss
Green Fluorite
Calcium Fluoride (CaF2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Clear Quartz
Silicon Dioxide (SiO2)
Lapis Lazuli (Tumbled)
Lazurite-dominated contact metamorphic rock
Lapis Lazuli
Na8[Al6Si6O24]Sn (Lazurite-rich metamorphic rock)
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
High-grade Metamorphic Gneiss
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Slate
Foliated Metamorphic Slate
Fuchsite
Cr-bearing Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Sandstone (likely Arkosic or Lithic Sandstone)
Sandstone (SiO2 predominant)
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Ironstone Concretion (Iron-rich Mudstone)
Siderite / Geothite concretion (FeCO3 / FeO(OH))
Red Quartzite (Strawberry Quartz)
Quartzite (SiO2 with iron oxide inclusions)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Note: Item is not a geological specimen
n/a