Sandstone
Arenite (primarily SiO2)
Category
Browse organic gem material (botanical) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily SiO2)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)
Sandstone (likely Arkosic or Lithic Sandstone)
Arenite (SiO2 based with mineral inclusions)
Sandstone
Arenite
Sandstone or Mudstone
Sedimentary Rock (Sandstone/Mudstone)
Quartzite Cobble
Quartzite (primarily SiO2)
Cinnabar in Quartz
Silicon Dioxide (SiO2) with Mercury Sulfide (HgS) inclusions
Red Sandstone
Arenite (primarily Quartz with Iron Oxide coating)
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
Banded Agate
Agate (Cryptocrystalline variety of Silica, SiO2)
Quartzite
Quartzite (SiO2)
Sandstone
Arenite (SiO2 primarily)
Blue Lace Agate (with Amethyst Geode center)
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
Quartz (Milky or Druzy Quartz)
Silicon Dioxide (SiO2)
Quartzite pebble
Quartzite (SiO2)
Asphalt (Bituminous Concrete)
Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)
Devil's Toenail
Gryphaea (extinct genus of foam oysters, typically composed of Calcite CaCO3)
Kunzite
Spodumene, LiAlSi2O6 (variety of spodumene)
Epidote (or Epidote-rich rock)
Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).
Decomposed Granite
Grano-diorite/Granite-residuum (SiO2 primary)
Concrete Paver (Artificial Cementitious Rock)
Hydrated Portland Cement Aggregate
Chert (Commonly known as Flint or River Pebble)
Microcrystalline Quartz (SiO2)
Muscovite Mica (in Quartz matrix)
Potassium aluminum silicate hydroxide fluoride (KAl2(AlSi3O10)(F,OH)2)
Banded Chert (River Stone)
Silicon Dioxide (SiO2)
Slate
Slate (foliated metamorphic rock)
Chert (and Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Common Opal variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert / Yellow Jasper
Silicon Dioxide (SiO2)
Malachite in Matrix
Copper Carbonate Hydroxide (Cu2CO3(OH)2)
Iron Meteorite
Siderite (Fe-Ni alloy, primarily Kamacite and Taenite)
Granite Pebble
Granite; primarily composed of Quartz (SiO2), Feldspar (KAlSi3O8), and Mica
Chert
Microcrystalline silica (SiO2)
Chert (Common Opal/Agate mixture)
Microcrystalline Quartz (SiO2)
Slate
Slate
Flint (Chert)
Silicon Dioxide (SiO2)
Quartz with Muscovite Mica
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)
Limestone
Calcium Carbonate (CaCO3)
Chert (Jasper/Flint variation)
Chert (SiO2)
Dragon Blood Jasper (Lizard Stone/Septarian Chalcedony)
Epidote with Black Hornblende and White Quartz mixture
Chrysocolla (with Quartz and Azurite)
Hydrated copper phyllosilicate mineral [Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)]
Limestone
Calcium carbonate (CaCO3)
Chert (specifically Flint)
Chert (SiO2)