Green Quartz (Prasiolite)
Crystalline Silicon Dioxide (SiO2) with iron impurities
Category
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
Green Quartz (Prasiolite)
Crystalline Silicon Dioxide (SiO2) with iron impurities
Sandstone
Arenite (SiO2 principal)
Concrete
Anthropogenic Conglomerate
Sandstone (Quartz-rich)
Arenite (SiO2)
Sandstone (Ferruginous)
Sandstone (primarily SiO2 with iron oxide cement Fe2O3)
Blue Topaz
Al2SiO4(F,OH)2
Titanium Aura Quartz
Titanium-coated Silicon Dioxide (SiO2)
Limestone (Concretionary or Tufa)
Calcium Carbonate (CaCO3)
Dyed Agate
Silicon Dioxide (SiO2)
Howlite and Purple Amethyst Druzy
Calcium Borosilicate Hydroxide (Howlite) and Silicon Dioxide (Quartz/Amethyst)
Yellow Quartz (Citrine/Gold Quartz)
Silicon Dioxide (SiO2)
Rough Citrine Quartz
Citrine (Silicon Dioxide, SiO2 with iron impurities)
Magnetite (potentially Hematite)
Magnetite (Fe₃O₄)
Conglomerate
Conglomeratic Sandstone
Granite
Granite
Sandstone (Quartzose Sandstone)
Clastic Terrigenous Sedimentary Rock (primarily SiO2)
Sandstone (Quartzite-rich Pebble)
Arenite (primarily SiO2)
Asphalt / Bituminous Aggregate
Bituminous mixture (Hydrocarbon-based sediment)
Citrine
Silicon Dioxide (SiO2)
Pearl (nacre)
Calcium Carbonate (mostly CaCO3 as Aragonite) and Conchiolin
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Granite
Granite (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Amethyst
Silicon dioxide with iron impurities (SiO2 + Fe3+)
Blue Howlite
Dyed Howlite (Ca2B5SiO9(OH)5)
Citrine
Silicon Dioxide (SiO2)
Amethyst (Rose-tinted variation)
Silicon Dioxide (SiO2) with trace iron impurities
Citrine
Silicon dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Aura Quartz
Titanium or Gold bonded Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Pearl
Calcium Carbonate (Aragonite) - CaCO3
Sandstone
Arenite (clastic sedimentary rock)
Sandstone (with minor quartz and possible clay components)
Clastic Sedimentary Rock (SiO2 dominated)
Sandstone
Clastic sedimentary rock (primarily SiO2)
River Stone (likely Siltstone or fine-grained Quartzite)
Sedimentary clastic rock containing SiO2 and iron oxides
Aluminum Slag
Anthropogenic Aluminum (Al)
Amethyst
Quartz (Silicon Dioxide with iron impurities), SiO2
Sandstone (Calcareous or Ferruginous)
Clastic sedimentary rock (SiO2 with CaCO3 or Fe2O3 cement)
Dyed Agate
SiO2 (Silicon Dioxide) - Chalcedony variety
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Magnetite
Iron(II,III) oxide (Fe3O4)
Chalk (Limestone variant)
Calcium Carbonate (CaCO3)