Oolite (Ooid)
Oolitic Limestone (chiefly CaCO3)
Category
Browse sedimentary (chemically precipitated mineral) specimens identified by the Rock Identifier community.
Oolite (Ooid)
Oolitic Limestone (chiefly CaCO3)
Sandstone with Ironstone Banding
Clastic Sandstone (composed of Quartz with Hematite/Limonite bonding)
Jasper and Quartz River Pebble
Silicon Dioxide (SiO2) with impurities
Limestone (with Chert)
Calcium Carbonate (CaCO3) / Microcrystalline Quartz (SiO2)
Aragonite (Onyx Marble)
Aragonite / Calcium Carbonate (CaCO3)
Dyed Pink Agate (Crackled)
Silicon Dioxide (SiO2) - Chalcedony variety
Gold
Native Gold (Au)
Chert (also known as Flint or Common Chalcedony)
Cryptocrystalline Silica (SiO2)
Chert (Yellow Jasper variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Limestone with Calcite Veining
Sedimentary Carbonate Rock (CaCO3)
Banded Calcite (often sold as 'Mexican Onyx' or 'Calcite Onyx')
Calcite (Calcium Carbonate, CaCO3)
Epidosite (Unakite-related)
Epidosite (predominantly Epidote, Ca2(Al2,Fe3+)(SiO4)3(OH))
Chert (Flint)
Silicon Dioxide (SiO2)
Bumblebee Jasper
Anhydrite-Aragonite mixture with Orpiment and Realgar
Gold in Quartz Matrix
Native Gold (Au) with Quartz (SiO2) and Slate/Shale
Jasper Shard / Chert
Silicon dioxide (SiO2)
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
Quartz Pebble
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline quartz (SiO2)
Chert Pebble
Chert (Microcrystalline Quartz, SiO2)
Chert Pebble with Inclusion
Microcrystalline Quartz (SiO2)
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Calcite with iron staining
Calcium Carbonate (CaCO3)
Green Calcite
Calcium Carbonate (CaCO3)
Small rounded pebble, likely quartz-rich river stone
Indeterminate; likely quartz/chert-bearing lithic clast
Limestone
Calcareous sedimentary rock (CaCO3)
Quartz Pebble
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
Quartz
Silicon Dioxide (SiO₂)
Howlite and Purpurite druzy
Calcium Borosilicate Hydroxide (Howlite) and Manganese Phosphate (Purpurite)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Weathered iron-rich rock, likely limonite-bearing sandstone or laterite
Limonite/goethite-rich ferruginous rock; composition commonly FeO(OH)·nH₂O with quartz and clay minerals
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Gold Flake
Native Gold (Au)
Blue Quartzite (Aventurine variety)
Silicon Dioxide (SiO2) with inclusions of Dumortierite or Magnesio-riebeckite
Flint / Chert with Cortex
Microcrystalline Quartz (SiO2)
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
Erythrite on Matrix
Cobalt Bloom (Co3(AsO4)2·8H2O)
Amethyst Geode
Amethyst (SiO2) - Silicon Dioxide with Trace Iron Impurities