Amazonite
KAlSi3O8 (Potassium aluminum silicate - blue-green variety of Microcline)
Category
Browse mineral and organic gemstone specimens identified by the Rock Identifier community.
Amazonite
KAlSi3O8 (Potassium aluminum silicate - blue-green variety of Microcline)
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)
Sunstone
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8
Turquoise in Matrix
Hydrous phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
Amazonite
Potassium Aluminum Silicate (KAlSi3O8)
Amber
Succinate (Fossilized Tree Resin)
Amber with Inclusion
Succiniferous fossil resin (C10H16O)
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Yellow Quartzite Pebble
Quartzite (primarily Silicon Dioxide - SiO2)
Lepidolite in Quartz (Obelisk)
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite)
Gneiss with Quartz Veining
Gneiss (High-grade regional metamorphic rock)
Jasper (Petrified Wood variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Limonite (Iron Ore)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Ironstone Concretion (Limonite/Hematite Nodules)
Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)
Gypsum (Wallboard/Drywall)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
Eudialyte in Matrix
Eudialyte [Na15Ca6(Fe,Mn)3Zr3(Si25O73)(O,OH,H2O)3(Cl,OH)2]
Shale
Fissile Mudstone (Shale)
Petrified Wood
Silicon Dioxide (SiO2) - Calcified / Silicified Wood
Amber
Amber (Amorphous Organic Hydrocarbon)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Chert (and Chalcedony)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcedony replacement)
Citrine
Silicon Dioxide (SiO2) with iron impurities
Chalcedony (Agatized Coral / Rough Chalcedony Node)
Silicon Dioxide (SiO2)
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
Sandstone
Arenite (primarily composed of SiO2)
Septarian Nodule
Septarian Concretion
Cubic Zirconia (CZ)
Zirconium dioxide (ZrO2)
Chert (often called Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Sandstone (with potential fossil inclusions)
Clastic sedimentary rock (primarily SiO2)
Agatized Fossil (Druzy Agate)
Silicon Dioxide (SiO2) replacing organic matter
Chert (Cherty Flint/Jasper variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Fossil Coral (Rugosa or Solitary Coral)
Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)
Chert (Holey Stone)
Microcrystalline Quartz (SiO2)
Garden Quartz
Included Quartz (SiO2 with accessory minerals such as Chlorite, Hematite, or Feldspar)
Limestone (Concretionary or Tufa)
Calcium Carbonate (CaCO3)
Banded Chert
Cryptocrystalline Quartz (SiO2)