Optical Calcite (Iceland Spar)
Calcium Carbonate (CaCO3)
Category
Browse sedimentary (secondary mineral) within igneous specimens identified by the Rock Identifier community.
Optical Calcite (Iceland Spar)
Calcium Carbonate (CaCO3)
Pyrite (Fools Gold)
Iron Sulfide (FeS2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Pyrite
Iron Sulfide (FeS2)
Pyrite
Iron Disulfide (FeS2)
Pyrite in Matrix
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Hematite with Magnetite
Iron Oxide (Fe2O3)
Quartz (Milky/Gray variety)
Silicon Dioxide (SiO2)
Chert / Flint
Chert (Silicon Dioxide, SiO2)
Quartz (Milky or Grainy Variety)
Silicon Dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)
Quartz with Mica inclusions (Gold-colored Mica)
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate (Phlogopite/Muscovite) inclusions
Jasper
Silicon Dioxide (SiO2) with impurities (mostly Iron Oxides)
Agate Geode
Silicon Dioxide (SiO2) - Banded Chalcedony
Chalcedony (Botryoidal/Agate nodule)
Microcrystalline Quartz (SiO2)
Howlite
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Banded Black Onyx (Chalcedony)
Silicon Dioxide (SiO₂)
Quartz Geode Pebble
Silicon Dioxide (SiO2)
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities
Sandstone (River Pebble)
Arenite (primarily SiO2)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Quartz (Clear / Rock Crystal)
Silicon Dioxide (SiO2)
Clear Quartz / Rock Crystal
Silicon Dioxide (SiO2)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Emerald in Matrix (Quartz/Schist)
Beryl (Be₃Al₂Si₆O₁₈) with Chromium/Vanadium impurities
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Carnelian (Red Chalcedony)
Silicon Dioxide (SiO2)
Chalcedony (Agate/Quartz variety)
Cryptocrystalline Quartz (SiO2)
Quartz (Milky/Clear Quartz)
Silicon Dioxide (SiO2)
Clear Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Quartz (Milky Variant)
Quartz (Silicon Dioxide, SiO2)
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (Smoky or Clear variety with inclusions)
Silicon Dioxide (SiO2)
Chalcedony (specifically Agate or Moonstone-like Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or Clear variety)
Silicon Dioxide (SiO2)