Sandstone (Pebble/Conglomerate fragment)
Sandstone (clastic sedimentary rock)
Sedimentary Rock
Category
Man Made Byproduct (Often Mistaken For Obsidian Or Emerald)
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Porphyritic Basalt or Diabase with Plagioclase Phenocrysts
Porphyritic Basalt or Diabase; Mineral: Plagioclase Feldspar
Igneous
Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)
Quartz (SiO₂)
Mineral
Jade
There are two distinct minerals classified as Jade: Jadeite (Na(Al,Fe3+)Si2O6) and Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2). Based on the image showing translucent, somewhat fibrous material, it is likely Nephrite.
Mineral
Strawberry Quartz
Quartz (SiO2) with inclusions of Goethite or Hematite
Mineral
Granite
Granite (a common term for a felsic intrusive igneous rock)
igneous
Quartz Geode/Cluster
Quartz (SiO2)
mineral
African Turquoise (Jasper)
Polychrome African Jasper (often marketed as 'African Turquoise' due to its color, but it is not true turquoise)
Rock
Chalcedony Geode
Chalcedony (SiO2) within a geode structure
Mineral Geode/Sedimentary or Volcanic related
Green Aventurine
Aventurine (a variety of Quartz, SiO2 with fuchsite inclusions)
Mineral
Sandstone
Arenite or Sandstone
Sedimentary Rock
Peridot and Citrine Gemstones (in a ring setting)
Peridot (Olivine: (Mg,Fe)2SiO4), Citrine (Quartz: SiO2)
mineral
Petrified Wood
Silicified wood, primarily composed of Quartz (SiO2)
Mineral, often found in sedimentary deposits
Quartz
Silicon Dioxide (SiO2)
Mineral
Quartz
Quartz (SiO₂)
Mineral
Diamond
Diamond (pure carbon, C)
Mineral
Corundum
Corundum (Al2O3)
Mineral
Malachite
Malachite (Cu2CO3(OH)2)
mineral
Chert (often referred to as 'Jasper' when red)
Chert (microcrystalline quartz, SiO₂)
Sedimentary rock
Milky Quartz
Quartz (SiO2)
Mineral
Labradorite (likely Black Labradorite or Larvikite)
Labradorite (Na,Ca)(Al,Si)4O8. If a rock, it is typically anorthosite, gabbro, or norite, or a variety of syenite called Larvikite if it is specifically from Larvik, Norway.
Mineral/Igneous Rock
Serpentine
Serpentine Group Minerals (e.g., Antigorite, Chrysotile, Lizardite)
Mineral, often found as a rock
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Fluorite (likely)
Calcium Fluoride (CaF2)
Mineral
Talc
Talc (Mg₃Si₄O₁₀(OH)₂)
Mineral
Granite
Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)
igneous
Quartz (Druzy) in host rock
SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)
Mineral
Quartz (likely milky quartz or a stained variety)
Silicon Dioxide (SiO₂)
Mineral
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Red Coral
Corallium rubrum (for precious red coral), although other species like Corallium japonicum and Paracorallium are also used.
Organic Gemstone (not a rock or mineral in the traditional sense, but bio-mineralized material)
Botryoidal Chalcedony
Chalcedony (SiO2)
Mineral
Quartz
Quartz (SiO2, Silicon Dioxide)
Mineral
Gneiss (likely)
Gneiss
Metamorphic
Calcite
Calcite (CaCO3)
Mineral
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sedimentary or Metamorphic (low grade)
Biotite Mica
K(Mg,Fe)3AlSi3O10(OH)2
Mineral in a matrix (likely quartz or feldspar)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
Banded Agate (variety of Chalcedony)
Agate (SiO2)
mineral
Quartz (likely Jasper or Chert variety)
Quartz (SiO₂)
Mineral
Quartzite
Quartzite
Metamorphic rock
White Jade / White Chalcedony
Nephrite Jade (Ca2(Mg,Fe)5Si8O22(OH)2) or Chalcedony (SiO2)
Mineral
Chert Pebble (Jasperoid/Flint)
Silicon Dioxide (SiO2) - cryptocrystalline quartz
Sedimentary