Amethyst
SiO2 (Silicon Dioxide) - Purple variety of Quartz
Category
Browse mineral, variety of chalcedony (microcrystalline quartz) specimens identified by the Rock Identifier community.
Amethyst
SiO2 (Silicon Dioxide) - Purple variety of Quartz
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide - SiO2)
Quartz (Milky/Rose variety)
Silicon Dioxide (SiO2)
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Impure Chalcedony
Mexican Crazy Lace Agate
Silicon Dioxide (SiO2) with iron and aluminum inclusions
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Orange Calcite Sphere
Calcium Carbonate (CaCO3)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)
Quartz (Milky/Rose Quartz variety)
Silicon Dioxide (SiO2)
Rutilated Quartz
Quartz (SiO2) with Rutile inclusions (TiO2)
Amazonite
Triklinic Potassium Feldspar (KAlSi3O8)
Jasper or Chert with Quartz Vugs
Silicon Dioxide (SiO2)
Quartz (Yellow/Milky variety)
Silicon Dioxide (SiO2)
Blue Calcite
Calcite (CaCO3)
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Milky Quartz in Conglomerate Matrix
Silicon Dioxide (SiO2) within Clastic Sedimentary Rock
Gneiss (specifically a Granitic Gneiss)
Gneiss (Composition: Quartz, Feldspar, Mica)
Chert (specifically Green Chert/Jasper)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Carnelian
Carnelian (Microcrystalline Quartz, SiO2)
Carnelian
Carnelian (Microcrystalline Quartz, SiO2)
Tiger's Eye (specifically Blue Tiger's Eye / Falcon's Eye)
Pseudomorph of Quartz after Crocidolite (SiO2)
Agatized Petrified Wood
Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood
Rose Quartz
SiO2 (Silicon Dioxide)
Sandstone with Quartz Vein
Arenite with Quartz (SiO2) Infilling
Rose Quartz
Rose Quartz (SiO₂)
Yellow Quartz / Quartz Pebble
Silicon Dioxide (SiO2)
Agate (Crazy Lace or Eye Agate)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Amazonite
Amazonite (KAlSi3O8 – a variety of Microcline, a Potassium Feldspar)
Quartz Pebble (Water-worn Quartzite)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Rough Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
Ferruginous Quartz
Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3/FeO(OH))
Citrine
Silicon Dioxide (SiO2) - Yellow Quartz variety
Chevron Amethyst
Crystalline Silicon Dioxide with Iron impurities (SiO2)