Chert (Hagstone/Adder Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
Chert (Hagstone/Adder Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Bismuth Crystal
Bismuth (Bi)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Chalcopyrite
Chalcopyrite (CuFeS2)
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2) with iron oxide inclusions
Yellow Quartz (Citrine Quartz or Yellow Chalcedony)
Silicon Dioxide (SiO2)
Gold Nugget
Native Gold (Au)
Blue Dyed Agate Geode
Chalcedony (cryptocrystalline Quartz), SiO2
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Citrine Quartz
Silicon Dioxide (SiO2)
Sandstone (Grooved/Weathered)
Arenite (composed primarily of Quartz and Lithic fragments)
Picture Jasper
Silicon Dioxide (SiO2)
Sandstone
Arenite
Dyed Howlite (simulating Lavender/Purple Jade or Charoite)
Howlite: Ca2B5SiO9(OH)5 (when natural)
Peacock Ore (Chalcopyrite)
Chalcopyrite (CuFeS2)
Pearl
Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)
Limonite Pseudomorph after Pyrite
Goethite/Limonite FeO(OH)·nH2O replacing Pyrite FeS2
Bornite (Peacock Ore)
Bornite (Cu5FeS4)
Slag (Industrial Glass)
Anthropogenic Vitreous Slag (Post-industrial byproduct)
Carborundum (Silicon Carbide)
Silicon Carbide (SiC) / Moissanite (natural form)
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Aventurine
Silicon Dioxide (SiO2) with inclusions
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Agate
Silicon dioxide (SiO2) - variety Chalcedony
Agate
Agate (Silicon Dioxide, SiO2)
Dragon Vein Agate
Chalcedony (cryptocrystalline silica, SiO2) variety Agate
Green Glass Slag
Amorphous Silicon Dioxide (SiO2) with metal oxide impurities
Silver (Native or Alloyed)
Ag (Argentum)
Slag
Anthropogenic Vitrification Product / Silicate Slag
Emerald in Matrix
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Black Onyx
Silicon Dioxide (SiO2)
Citrine Geode Fragment
Citrine (Silicon Dioxide with Iron Impurities), SiO2
Chert (Flint variety)
Chert (Cryptocrystalline Quartz, SiO2)
Citrine Quartz
Crystalline Silicon Dioxide (SiO2) with Ferric Iron impurities
Apache Tear (Obsidian)
Obsidian (Hydrated Amorphous Silica, SiO2 + MgO/Fe3O4)
Chrysoberyl (Cyclic Twin)
Beryllium Aluminum Oxide (BeAl2O4)
Blue Howlite (Dyed)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Smoky Quartz (with Hematite inclusions)
Silicon Dioxide (SiO2)
Agate Slices and Clear Quartz Points
Agate (SiO2 Chalcedony) and Clear Quartz (SiO2 Crystalline)
Dyed Agate Geode (Pink/Magenta)
Silicon Dioxide (SiO2) - variety of Chalcedony/Quartz