Blue Agate (Dyed Chalcedony)
Silicon Dioxide (SiO2)
mineral
Category
Synthetic Or Natural Fiber
Browse synthetic or natural fiber specimens identified by the Rock Identifier community.
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
mineral
Chert (White Variety)
Silicon Dioxide (SiO2)
sedimentary
Citrine
Silicon Dioxide (SiO2) with iron impurities
Mineral
Citrine
Silicon Dioxide (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Amethyst
SiO2 (Silicon Dioxide with Iron impurities and irradiation)
mineral
Grey Quartz (likely Smoky Quartz or Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Citrine
Silicon Dioxide (SiO2) - Macrocrystalline Quartz variety
mineral
Slag (Industrial Byproduct)
Ferrous/Non-ferrous Silicate
igneous (artificial/anthropogenic)
Smoky Quartz
Quartz (Silicon Dioxide) - SiO2
mineral
Aura Quartz
Titanium-coated Silicon Dioxide (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2)
mineral
Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Polished Basalt
Basalt (Mafic volcanic rock)
Igneous
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
igneous
Amethyst
SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Aventurine Quartz
Silicon Dioxide (SiO2) with Fuchsite inclusions
metamorphic
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Green Aventurine
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
mineral
Sandstone (likely Quartzose)
Arenite (primarily SiO2)
sedimentary
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Chevron Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Concrete
Anthropogenic Sedimentary Conglomerate (Cement mixture: typically Ca2SiO4, Ca3SiO5, Ca3Al2O6)
sedimentary (artificial)
Aura Quartz (Pink/Rose Aura Quartz)
Silicon Dioxide (SiO2) bonded with Platinum and/or Silver
mineral
Ironstone (Limonitic Shale)
Ferruginous Siltstone / Goethite-rich Sedimentary Rock
sedimentary
Sandstone (likely Arkosic or Quartzose)
Sandstone (SiO2 dominated)
sedimentary
Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide staining/cementing)
sedimentary
Asphalt (Road Aggregate)
Bituminous Conglomerate / Asphalt Concrete
Anthropogenic (Man-made)
Sandstone (Red Sandstone)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide)
sedimentary
Fluorite (Polished Point/Tower)
Calcium Fluoride (CaF2)
mineral
Moonstone (Variety of Orthoclase Feldspar)
KAlSi3O8 (Potassium Aluminum Silicate)
mineral
Eye Agate
Silicon Dioxide (SiO2) - Banded Chalcedony
mineral
Fluorite (Rainbow Fluorite Point)
Calcium Fluoride (CaF2)
mineral
Sandstone
Arenite (primarily SiO2 with various cementing agents)
sedimentary
Dyed Pink Quartzite (Jadeite Simulant)
Silicon Dioxide (SiO2) with organic dye
metamorphic
Rose Quartz and Milky Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone
Arenite (SiO2 based)
sedimentary
Ferruginous Slag (Iron Smelting Byproduct)
Anthropogenic Vitreous Silicate (often containing Fayalite: Fe2SiO4)
Mineraloid/Anthropogenic (Technofossil)
Blue Agate (Dyed)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Granite (Weathered River Rock)
Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous