Agate
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Category
Sedimentary Rock (Technically A Microcrystalline Quartz Mineral Aggregate)
Browse sedimentary rock (technically a microcrystalline quartz mineral aggregate) specimens identified by the Rock Identifier community.
Learn about Sedimentary Rock (Technically A Microcrystalline Quartz Mineral Aggregate) in the encyclopedia
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Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz Vein in Host Rock (Likely Slate or Shale)
Hydrothermal Quartz (SiO2) in Pelitic host rock
metamorphic
River Pebble (Quartz-rich)
Silicon Dioxide (SiO2) with various inclusions
sedimentary
Hagstone (Adder Stone)
Chert or Sedimentary pebble with natural perforation
sedimentary
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
mineral
Chert (and/or Siltstone River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Fossilized Brachiopod or Gastropod in Chert/Limestone
Phylum Brachiopoda / Mollusca
fossil
Weathered quartz-rich river pebble
Likely quartzite or siliceous sandstone; exact identification requires testing
sedimentary
Quartz-rich breccia or silicified rock
Microcrystalline quartz (SiO₂) with iron-oxide staining and darker host-rock fragments
metamorphic
Chalcedony
Cryptocrystalline Quartz (SiO2)
mineral
Chalcedony
Silicon Dioxide (SiO2)
mineral
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert
Silicon dioxide (SiO2)
sedimentary
Chalcedony (Agate / Chert)
Silicon Dioxide (SiO2)
mineral
Quartz-veined Limestone
Sedimentary limestone with hydrothermal quartz/calcite veins (CaCO3 / SiO2)
sedimentary
Sandstone (Quartzose Sandstone)
Sandstone (SiO2 dominant composition)
sedimentary
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)
sedimentary
Dendritic Jasper
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
sedimentary
Chert (Flint nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Giallo Ornamental Granite
Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica)
igneous
Sandstone (with Chert/Quartzite)
Arenite (SiO2 primarily)
sedimentary
Chert (or Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Pebble
Silicon dioxide (SiO2)
sedimentary
Mookaite Jasper
Silicified Radiolarite (SiO2)
sedimentary
Red Jasper (or Banded Jasper)
Silicon Dioxide (SiO2 with Hematite impurities)
mineral
White Chalcedony
Silicon Dioxide (SiO2)
mineral
Chert nodules in Limestone
Microcrystalline Quartz (SiO2) in Calcium Carbonate (CaCO3) matrix
sedimentary
Brecciated Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2
sedimentary
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Tumbled agate or chalcedony
Microcrystalline quartz (SiO₂), likely yellow-brown chalcedony/agate
mineral
Chert (Jasper/Flint Pebble)
Microcrystalline quartz (SiO2)
sedimentary
Quartz (Chert/Chalcedony flake)
Silicon Dioxide (SiO2)
mineral
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
mineral
Mixed River Pebbles and Jasper
Siliciclastic sediment and microcrystalline quartz
sedimentary
River Pebble (Siltstone / Sandstone Pebble)
Sedimentary Rock (Quartz, Feldspar, Clay Minerals)
sedimentary
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Bone Chunk
Permineralized Vertebrate Bone (indeterminant)
fossil
Agate (Carnelian / Chalcedony)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
mineral
Quartz / Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
mineral
Banded Sandstone
Quartz-rich Arenite Sandstone
sedimentary
Quartz Pebble
Silicon dioxide (SiO2)
sedimentary