Obsidian
Volcanic Glass (70% or more SiO2)
Category
Browse man made rock (technosol) specimens identified by the Rock Identifier community.
Obsidian
Volcanic Glass (70% or more SiO2)
Diamond Plate (Steel)
Alloyed Carbon Steel or Aluminum with 'Durbar' pattern
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
Chert
Chert (microcrystalline quartz)
Engineered Quartz Stone
Agglomerated Quartz (SiO2 + Polymer Resin)
Diamond
Diamond (pure Carbon, C)
Sandstone
Arenite
Coquina
Bioclastic Limestone
US Penny
Cuprum (Copper: Cu) and Zincum (Zinc: Zn) Alloy
Asphalt Concrete
Bituminous Concrete / Asphaltic Composite
Limonite (Iron Ore)
Hydrous Iron Oxide (goethite, lepidocrocite)
Quartz
Silicon dioxide (SiO₂)
Diamond
Cubic carbon (C)
Marble
Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Granite Cobble/Pebble
Granite
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Diabase (Greenstone)
Diabase (also known as Dolerite)
Red Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Quartz (Engineered Quartz Surface)
Silicon Dioxide (SiO2) based composite
Faceted Glass (Costume Jewelry)
Amorphous Silicon Dioxide with colorants (Glass)
Obsidian
Volcanic Glass (SiO2)
Chert (Cherty Shale / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Bog Iron / Limonite Concretion
Goethite/Limonite mixture (FeO(OH)·nH2O)
Diamond (in Jewelry)
Carbon (C)
Pearl
Biogenic CaCO3 (Aragonite and Calcite)
Diamond
Diamond (pure Carbon, C)
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Obsidian
Obsidian (volcanic glass)
Synthetic Costume Accessory (Non-Geological)
Polyester and Acrylic Fiber (Anthropogenic polymer)
Blue Goldstone
Aventurine Glass (Silicon Dioxide infused with Cobalt/Copper)
Sea Glass (Cobalt Blue)
Amorphous Silica (Glass with Cobalt additives)
Porcelain (Kaolin-based)
Alumina silicate ceramic (composed primarily of Kaolinite: Al2Si2O5(OH)4)
Granite
Granite (Mainly Quartz SiO2, Feldspar KAlSi3O8, and Mica KAl2(AlSi3O10)(OH)2)
Smoky Quartz
Smoky Quartz (SiO2)
Pearl and Garnet Glass
Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
Pearl
Calcium carbonate (CaCO3) - mainly Aragonite with Conchiolin
Diamond (in a jewelry setting)
Cubic Carbon (C)
Chert (Chert / Flint Variety)
Microcrystalline / Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Diamond
Diamond (pure carbon C)