Diorite
Intermediate plutonic igneous rock
Category
Browse mineral based human made alloy specimens identified by the Rock Identifier community.
Diorite
Intermediate plutonic igneous rock
Amethyst or Smoky Quartz Geode Slice
Crystalline Silicon Dioxide (SiO2) with iron impurities
Diamond (or Cubic Zirconia)
Carbon (C) or Zirconium Dioxide (ZrO2)
Opalite
Man-made Synthetic Glass (Silicon Dioxide with metal additives)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Fossilized Shark Tooth (Sand Tiger)
Carcharias sp. (Fossilized Tooth)
Muscovite Mica
Muscovite: KAl2(AlSi3O10)(OH)2
Slate
Metamorphic pelitic rock
Granite
Felsic intrusive igneous rock (Quartz, Feldspar, Mica)
Mica Schist or Muscovite
KAl2(AlSi3O10)(OH)2
Porphyritic Basalt
Basalt (porphyritic texture)
Quartz Fragment
Silicon Dioxide (SiO2)
Granite Pebble
Granite (Plutonic Igneous Rock)
Vesicular Basalt
Basalt (Mafic volcanic rock)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Sandstone (Red/Brown Variety)
Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)
Weathered granite (feldspathic, iron-stained granite)
Granite; primarily quartz, potassium feldspar, plagioclase feldspar, and minor mica/amphibole. Exact identification is uncertain from a single photograph.
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Obsidian
Obsidian (Volcanic Glass)
Chert nodules in Limestone
Microcrystalline Quartz (SiO2) in Calcium Carbonate (CaCO3) matrix
Chert (Iron-stained)
Microcrystalline quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (White Chert)
Silicon Dioxide (SiO2)
Chert (Flint) Pebble
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert / Flint Nodules
Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Yellow calcite (tumbled honey or lemon calcite)
Calcite, calcium carbonate (CaCO₃), likely a yellow/orange calcite variety
Fossilized Ray Barb (Stinger) Fragment
Myliobatiformes indet. (Fossil stingray spine)
Yellow Ochre (Limonite)
Limonite (FeO(OH)qnH2O)
Clear quartz sphere
Quartz (silicon dioxide, SiO₂)
Opalite
Synthetic Opalized Glass / Man-made Glass
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Diamond
C (Native Carbon)
Dyed Blue Agate (Dragon Vein Agate)
Silicon Dioxide (SiO2) with artificial cobalt/organic dyes
Diamond
Native Carbon (C)
Limonite
Hydrous ferric oxides (FeO(OH)·nH2O)
Chert (Flint with Iron Staining)
Silicon Dioxide (SiO2)
Chert / River Jasper
Silicon Dioxide (SiO2)
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Quartzite with Calcite Accretion
Metamorphosed Quartz Sandstone (SiO2 with CaCO3 coating)