Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Category
Sedimentary (Primary) With Artificial Modification
Browse sedimentary (primary) with artificial modification specimens identified by the Rock Identifier community.
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Limonite (Iron Ore)
FeO(OH)·nH2O
mineral
Silver (Native Element)
Ag (Argentum) - 90% Silver, 10% Copper alloy in specimen
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Quartz (Grain)
Silicon Dioxide (SiO2)
mineral
Moonstone
Orthoclase (KAlSi3O8) or Albite (NaAlSi3O8)
mineral
Placer Gold Nugget
Native Gold (Au)
mineral
Amethyst (vibrant lilac/purple variety)
Silicon Dioxide (SiO2) with iron impurities
mineral
Gold and Diamond
Native Gold (Au) and Diamond (C)
mineral
Red Tiger Eye (or Polished Jasper Gneiss)
Silicon dioxide with crocidolite inclusions (SiO2)
metamorphic
Concrete / Anthropogenic Conglomerate
Man-made composite material (Portland cement, aggregate, and water)
not a natural rock
Gold (10K Alloy)
Aurum (Au) with alloying metals (Cu, Ag, Zn)
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Peridotite (Dunite)
Olivine-rich Peridotite ((Mg,Fe)2SiO4)
igneous
Green Calcite
Calcite (CaCO3)
mineral
Blue Sapphire
Corundum (Al2O3)
mineral
Tiger's Eye
Silicon Dioxide with inclusions (SiO2)
mineral
Gossan (with secondary copper minerals)
Iron-rich oxidized rock cap (Limonite/Goethite with Malachite/Chrysocolla inclusions)
metamorphic
Granitoid (Granite/Gneiss mix)
Phaneritic Felsic Igneous Rock
igneous
Quartz Vein in Granite
Crystalline Silicon Dioxide (SiO2) in Granitic Matrix
mineral/igneous
Olivine Diabase (Microgabbro)
Diabase or Dolerite with Olivine
igneous
Goethite
Goethite (FeO(OH))
mineral
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
mineral
Scoria
Scoriaceous Basalt
igneous
Granite Cobble
Phaneritic Felsic Igneous Rock
igneous
Quartz with Mica (Pegmatite)
Quartz (SiO2) and Muscovite (KAl2(AlSi3O10)(OH)2)
igneous
Granite Cobble
Phaneritic Felsic Igneous Rock
igneous
Serpentine
Antigorite/Lizardite/Chrysotile group, Mg3Si2O5(OH)4
metamorphic
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Milky Quartz with Inclusions
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz (Water-worn Pebble)
Silicon Dioxide (SiO2)
mineral
Aragonite
Aragonite (Calcium Carbonate - CaCO3)
mineral
Quartz Pebble (often referred to as 'Sea Glass' or 'River Stone' when worn smooth)
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (Mafic Extrusive)
igneous
Fuchsite (Chrome Mica)
Cr-bearing Muscovite - K(Al,Cr)2(AlSi3O10)(OH)2
mineral
Soapstone (Steatite)
Steatite (primarily Talc: Mg3Si4O10(OH)2)
metamorphic
Pink Granite
Phaneritic Felsic Igneous Rock (composed of orthoclase, quartz, and plagioclase)
igneous
Man-made Polished Porcelain Tile (Artificial Geologic Lookalike)
Fused Silicate Ceramic with Alumina (Synthetic Kaolinite derivative)
Synthetic (Ceramic)
Red Jasper
Red Jasper (variety of Chalcedony, SiO₂)
Mineral
Quartz (Microcrystalline Gravel)
Silicon Dioxide (SiO2)
mineral
Diamond (in a metal ring setting)
Diamond (Pure Carbon, C)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous