Chert / Flint
Microcrystalline Quartz (SiO2)
Category
Browse antropogenic rock (man made) specimens identified by the Rock Identifier community.
Chert / Flint
Microcrystalline Quartz (SiO2)
Flint
SiO2 (Cryptocrystalline Quartz)
Chert / Flint
Silicon Dioxide (SiO2)
Brecciated Jasper
Brecciated Jasper (Microcrystalline Quartz / SiO2)
Green Aventurine
Silicon Dioxide (SiO2+KAl2(AlSi3O10)(OH)2)
Gabbro
Gabbro (Mg, Fe)2Si2O6 / (Ca, Na)(Al, Si)4O8
Chert (with Quartz)
Microcrystalline Quartz (SiO2)
Diamond (in Jewelry)
Carbon (C)
Quartz
Silicon dioxide (SiO₂)
Tumbled chalcedony (likely moss or dendritic agate)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
Quartzite
Metamorphic Quartzite
Green Quartzite
Metamorphic Quartz Sandstone (SiO2)
Red Quartzite
Quartzite (Metamorphosed Quartz Arenite)
Diamond
Carbon (C)
Chert (Yellow Jasper/Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert
Chert (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Obsidian
Obsidian (volcanic glass)
Limestone Pebble
Sedimentary Calcium Carbonate (CaCO3)
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Tumbled blue-green stone, likely chrysocolla or dyed chalcedony
Probable chrysocolla (hydrated copper aluminosilicate; variable composition), though appearance could also represent dyed chalcedony
Blue-green chrysocolla rough specimen
Chrysocolla, hydrated copper aluminosilicate; commonly associated with malachite, quartz, and limonite
Obsidian
Volcanic glass (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Bog Iron / Limonite Concretion
Goethite/Limonite mixture (FeO(OH)·nH2O)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (primarily SiO2 with Fe2O3)
Quartzite
Metamorphic Quartzite (SiO2)
Granite
Granite (Mainly Quartz SiO2, Feldspar KAlSi3O8, and Mica KAl2(AlSi3O10)(OH)2)
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Diamond
Carbon (C)
Diamond
Carbon (C)
Chert
Microcrystalline Quartz (SiO2)
Chert (Siltstone / Flint)
SiO2 (Cryptocrystalline Quartz)
Banded Jasper / Chert Beach Pebble
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert / Flint
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Green Quartzite
Metamorphic Quartzite (often colored by chromium-bearing minerals or fuchsite)
Flint / Chert
Microcrystalline quartz (SiO2)
Pearl and Garnet Glass
Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass
Smoky Quartz
Smoky Quartz (SiO2)
Pearl
Organic gemstone (Calcium carbonate - CaCO3)