Amethyst Geode
Amethyst (Silicon Dioxide), Formula: SiO2
mineral
Category
Mineral Precipitate (Anthropogenic Context)
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Learn about Mineral Precipitate (Anthropogenic Context) in the encyclopedia
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Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Ferruginous Sandstone
Sandstone with Iron Oxide (Limonite/Goethite)
sedimentary
Honey Calcite
Calcium Carbonate (CaCO3)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Honey Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Banded Agate
Chalcedony (Silicon Dioxide, SiO2)
mineral
Honey Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Quartz (Milk or Clear)
Silicon Dioxide (SiO2)
mineral
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) in matrix
mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Amethyst
Silicon Dioxide (SiO2) with trace Iron (Fe)
mineral
Agate (Chalcedony)
Cryptocrystalline Quartz (SiO2)
mineral
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Fluorite (likely Fluorite on Quartz/Matrix)
Calcium Fluoride (CaF2)
mineral
Yellow Calcite (Banded Calcite)
Calcium Carbonate (CaCO3)
mineral
Quartz (Milky or Citrine-tinted)
Silicon Dioxide (SiO2)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
White Quartz
Silicon Dioxide (SiO2)
mineral
Ocean Jasper
Orbicular Jasper (Silicon Dioxide, SiO2)
mineral
Milky Quartz Vein in Host Rock
Silicon Dioxide (SiO2)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Chalcedony Nodule (Carnelian/Agate)
Chalcedony (Silicon Dioxide, SiO2)
mineral
Quartz Geode
Quartz (Silicon Dioxide, SiO2) Geode
sedimentary
Moqui Marble (Sandstone Concretion)
Hematite-cemented Sandstone (Fe2O3 + SiO2)
sedimentary
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
sedimentary
Banded Onyx (Cave Calcite)
Calcite (CaCO3), often called Mexican Onyx or Travertine
sedimentary
Septarian Nodule
Septarian Concretion (CaCO3 with Siderite/Calcite)
sedimentary
Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metal oxide colorants
Anthropogenic (Man-made)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
igneous
Dendritic Siltstone (or Mudstone)
Siltstone with Manganese Oxide dendrites
sedimentary
Bog Iron (Limonite Concretion)
Limonite (FeO(OH)·nH2O)
sedimentary
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
sedimentary
Sandstone with Iron Staining
Arenite (SiO2 based with Fe2O3 staining)
sedimentary
Septarian Nodule
Septarian concretion (Complex mixture of Siderite/Limestone, Calcite, and Aragonite)
sedimentary