Chalcedony (Agate/Carnelian)
Cryptocrystalline Silicon Dioxide (SiO2)
mineral
Category
Mineral (Specifically A Mineraloid)
Browse mineral (specifically a mineraloid) specimens identified by the Rock Identifier community.
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Granitic Pegmatite
Granite Pegmatite (coarse-grained intrusive igneous rock)
igneous
Garnet (specifically Almandine or Pyrope)
Almandine: Fe3Al2(SiO4)3 or Pyrope: Mg3Al2(SiO4)3
mineral
Chalcedony (specifically Agate or Moonstone-like Quartz)
Silicon Dioxide (SiO2)
mineral
Chalcedony (specifically Agate or Carnelian pebble)
Chalcedony (Microcrystalline Quartz, SiO2)
mineral
Quartz (specifically Milky Quartz/Quartzite)
Silicon Dioxide (SiO2)
Mineral
Quartz (specifically Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (composition predominately plagioclase feldspar and pyroxene)
igneous
Sandstone (specifically Flagstone)
Arenite (primarily composed of SiO2)
sedimentary
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Granite
Phaneritic plutonic rock (approx. 20-60% quartz, 35-90% feldspar)
igneous
Banded Agate (specifically Carnelian Agate)
Silicon Dioxide (SiO2)
mineral
Fossil Coral
Hexagonaria or Rugose coral fossil in limestone/silica matrix
fossil
Porphyry
Porphyritic Andesite/Basalt
igneous
Jasper (specifically Yellow or Bumblebee-like Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary
Amber
Succinite (specifically for Baltic Amber), Formula: C10H16O
Organic Gemstone (often associated with Sedimentary sequences)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Pink Granite
Phaneritic intrusive igneous rock (high Orthoclase Feldspar content)
igneous
Mookaite Jasper
Radiolarite (Silicified radiolarian chert)
sedimentary
Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
Mineral
Agate (specifically Lake Superior Agate style or Banded Chalcedony)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Chert (White Chert / Flint)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
sedimentary
Amazonite
Microcline (KAlSi3O8, a variety of Potassium Feldspar)
mineral
Citrine Quartz
Citrine (Silicon Dioxide, SiO2)
mineral
Tumbled Moonstone and Amazonite Chips
Orthoclase (KAlSi3O8) and Microcline (KAlSi3O8) of the Feldspar Group
mineral
Milky Quartz
Quartz (Silica / Silicon Dioxide), SiO2
mineral
Quartz (Milky or Cloudy Quartz)
Silicon Dioxide (SiO2)
mineral
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Banded Agate / Lace Agate
Agate (Silica/Quartz) - SiO2
mineral
Mookaite Jasper
Silicified Radiolarite (SiO2)
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Conglomerate (Puddingstone)
Conglomerate (specifically, clastic sedimentary rock)
Sedimentary
Green Moss Agate
Silicon Dioxide (SiO2) with Mineral Inclusions
sedimentary
Basalt (with possible alteration or lichen)
Mafic volcanic rock (primarily Plagioclase and Pyroxene)
igneous
Basalt with Epidote Veins
Mafic Igneous Rock (Basalt)
igneous
Sandstone
Arenite (specifically Iron-stained Quartz Sandstone)
sedimentary
Granite (specifically Pink Granite)
Phaneritic Plutonic Rock (High Potassium Feldspar Granite)
igneous
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
mineral
Amphibolite (specifically Hornblende Schist/Gneiss)
Amphibole-rich Metamorphic Rock
metamorphic
Agate (specifically crazy lace agate / orbicular agate node)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Opalite
Synthetic Opalized Glass
gemstone
Banded Agate with Druzy Quartz
Agate (Silicon Dioxide - SiO2)
mineral