Crushed Limestone
Sedimentary Carbonate Rock (CaCO3)
sedimentary
Category
Sedimentary Rock (Specifically A Concretion Or Possibly A Geode)
Browse sedimentary rock (specifically a concretion or possibly a geode) specimens identified by the Rock Identifier community.
Conglomerate
Clastic Sedimentary Rock (Conglomerate)
sedimentary
Conglomerate
Conglomeratic Sandstone / Sedimentary Breccia
sedimentary
Porphyritic Basalt or Diabase with Plagioclase Phenocrysts
Porphyritic Basalt or Diabase; Mineral: Plagioclase Feldspar
Igneous
Chert (Gravel Bit)
Microcrystalline silica (SiO2)
sedimentary
Chalcedony (Banded/Mottled Variety)
Chalcedony (a cryptocrystalline variety of Quartz, SiO2)
Mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Quartz Druze (on Matrix)
Silicon Dioxide (SiO2)
mineral
Crushed Limestone (Gravel)
Calcium Carbonate (CaCO3)
sedimentary
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
metamorphic
Pink Granite
Phaneritic Felsic Igneous Rock
igneous
Chert (specifically Jasper/Brown Chert)
Silicon Dioxide (SiO2)
sedimentary
Yellow Chert (Jasper)
Chalcedony (SiO2) with iron oxide inclusions
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Ethiopian Fire Opal
Hydrated Silica (SiO2·nH2O)
mineral
Limestone
Sedimentary Calcite (CaCO3)
sedimentary
Marble
Recrystallized Calcite (CaCO3) Rock
metamorphic
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)
mineral
Banded Agate (Agatized Geode Slice)
Silicon Dioxide (SiO₂)
mineral
Quartz Geode (Cracked)
Silicon Dioxide (SiO2)
mineral
Quartz Geode Fragment
Silicon Dioxide (SiO2) in a Sedimentary Host
mineral
Pink Granite
Phaneritic Felsic Igneous Rock (composed primarily of K-Feldspar, Quartz, and Plagioclase)
igneous
Amethyst Geode (Carved)
Amethyst (Violet Crystalline Quartz - SiO2)
mineral
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Yellow Ochre / Limonite
Limonite (FeO(OH)·nH2O)
Mineral
Celestite (Celestine)
Strontium Sulfate (SrSO4)
mineral
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Conglomerate
Conglomerate rock
sedimentary
Amethyst (Tumbled Stone)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
mineral
K2 Azurite Granite / K2 Stone
Granite (igneous rock) with Azurite inclusions (mineral)
igneous
Citrine (Heat-treated Amethyst)
Citrine Quartz (SiO2)
Mineral (Tectosilicate)
Quartz
Quartz (SiO2)
Mineral
River Rocks (Black)
Various lithologies (e.g., basalt, chert, obsidian for black varieties), mechanically rounded clasts
Sedimentary
Pink Granite / Gneiss
Felsic Plutonic Rock (Granite) with Gneissic banding
igneous / metamorphic
Agate (specifically, a slice of a Blue Lace or Chalcedony Agate nodule)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Amygdaloidal Basalt with Agate/Chalcedony Infills
Amygdaloidal Basalt (Composition: SiO2 and (Mg,Fe)2SiO4 in matrix; SiO2 in amygdule)
igneous
Amethyst (as a jewelry accent)
Amethyst (Silicon Dioxide SiO2 with Iron impurities)
mineral
Mookaite Jasper
Siliceous sedimentary rock (variety of Jasper/Chert)
Sedimentary Rock
Feldspar-rich Granite (Pink Granite)
Phaneritic Felsic Igneous Rock
igneous
Amethyst (Tumbled Chips)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
mineral
Sandstone (likely Graywacke or Arkose variant)
Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)
sedimentary
Diabase
Diabase (also known as Dolerite)
igneous