Chalcedony (specifically Agate or Flint)
Silicon Dioxide (SiO₂)
Mineral
Category
Mineral Based Human Made Alloy
Browse mineral based human made alloy specimens identified by the Rock Identifier community.
Banded Agate (Onyx Variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
mineral
Basalt with Limonite stains
Extrusive mafic igneous rock; Limonite (FeO(OH)·nH2O)
igneous
Amethyst Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone Pebble
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Fossilized Shark Tooth
Fossilized Elasmobranchii tooth (likely Odontaspis or Carcharias)
sedimentary
Basalt
Basalt (composition of plagioclase feldspar and pyroxene)
igneous
Mica (likely Muscovite)
Muscovite / KAl2(AlSi3O10)(OH)2
mineral
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
mineraloid
Rough Green Sapphire (Corundum)
Corundum (Al2O3 - Aluminum Oxide with trace elements)
mineral
Biotite (Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Precious Opal
Hydrated Silica (SiO2·nH2O)
mineral
Aquamarine
Beryl (Be3Al2Si6O18)
mineral
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Basalt with Quartz Vein
Mafic Igneous Rock (SiO2 filling)
igneous
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
mineral
Graphite
Graphite (Native Carbon), Formula: C
Metamorphic
Vesicular Basalt
Vesicular Basalt (Aphanitic Mafic Rock)
igneous
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Slag
Anthropogenic Vitrification Product / Silicate Slag
Anthropogenic (Man-made industrial byproduct)
Lepidolite
Lepidolite - K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
mineral
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)
mineral
Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 with inclusions)
sedimentary
Wishing Stone (Basalt with Quartz Vein)
Basalt containing a microcrystalline quartz (SiO2) or calcite vein
igneous
Granite
Phaneritic Felsic Igneous Rock (primarily Quartz, Alkali Feldspar, and Plagioclase)
igneous
Sandstone (Quartz Arenite)
Sandstone (SiO2 with possible mineral cements)
sedimentary
Granitoid (Granite/Gneiss)
Granitoid silicate rock, primarily quartz and feldspar
igneous/metamorphic
![Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral](https://media.rockidentification.com/81546651-32fa-4148-838a-c2bca7c29bba-thumbnail.jpg)
Turquoise
Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]
mineral
Titanium Aura Quartz (Aura Quartz)
Titanium-coated Silicon Dioxide (SiO2)
mineral
Chert (often called Flint when dark or found in chalk)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Banded Agate (specifically Mexican Lace Agate variety appearance)
Silicon Dioxide (SiO2 / Chalcedony)
mineral
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe/Chlorite)
mineral
Mica (specimen appears to be Muscovite or Phlogopite)
Phyllosilicate mineral; Muscovite: KAl2(AlSi3O10)(F,OH)2
Mineral (Found in Igneous and Metamorphic rocks)
Basalt with Calcite Veining
Aphanitic Mafic Igneous Rock (Basalt) with CaCO3
igneous
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si)4O10(F,OH)2)
mineral
Quartz with Muscovite Mica
SiO2 with KAl2(AlSi3O10)(OH)2
mineral group