Greywacke (likely)
Greywacke (a type of sandstone)
Category
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
Greywacke (likely)
Greywacke (a type of sandstone)
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Smoky Quartz
Silicon Dioxide (SiO2)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Chrysocolla
Chrysocolla, (Cu, Al)2H2Si2O5(OH)4·nH2O
Turquoise
Hydrated phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Fossilized Wood (Petrified Wood)
Silicified Wood (primarily quartz/chalcedony replacing organic matter)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Sodalite
Na8(Al6Si6O24)Cl2
Olivine
Magnesium Iron Silicate ((Mg, Fe)₂SiO₄)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Green Banded Chert (Agate/Jasper)
Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite
Labradorite (Carved)
(Ca, Na)(Al, Si)4O8
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxides)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Milky or Smoky Quartz)
Quartz (Silicon Dioxide, SiO2)
Amazonite
K(AlSi3O8) - Microcline variant
Aquamarine
Beryl (Be3Al2Si6O18 with iron impurities)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
Smoky Quartz Cluster
Smoky Quartz (Silicon Dioxide - SiO2)
Labradorite (Feldspar)
Labradorite: (Ca,Na)(Al,Si)4O8
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Prehnite
Prehnite Ca2Al2Si3O10(OH)2
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Pink Tourmaline in Quartz Matrix
Elbaite (Na(Li,Al)3Al6(Si6O18)(BO3)3(OH)4) in Quartz (SiO2)
Black Star Diopside
Diopside (CaMgSi2O6) with asterism
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Amethyst
Silicon Dioxide (SiO2 with iron impurities)
Dolomite on Prehnite (Saddle-shaped Dolomite)
Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]
Amazonite
Triklinic Potassium Feldspar (KAlSi3O8)
Rough Emerald/Green Beryl
Beryl (Be3Al2(SiO3)6) with trace amounts of Chromium or Vanadium
Olivine (Peridot)
Olivine (Magnesium Iron Silicate, (Mg,Fe)2SiO4)
Septarian Nodule (Dragon Stone)
Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)
Biotite Mica
K(Mg,Fe2+)3(Al,Fe3+)Si3O10(OH,F)2
Unidentified Rock Fragment
Unknown
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Olivine in Basalt (Peridotite Xenolith)
Forsterite-rich Olivine (Mg2SiO4) in Aphanitic Basalt
Shale or Mudstone (Based on appearance)
Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Pink Feldspar (Orthoclase)
Orthoclase Feldspar (KAlSi3O8)
Amethyst
Amethyst (Silica mineral, SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)