Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Jasper (Chert)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Zircon
Zircon (Zirconium Silicate, ZrSiO4)
Quartz Pebble (Chert/Chalcedony)
Silicon Dioxide (SiO2)
Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO₂)
Clear Quartz Fragment
Quartz (Silicon Dioxide, SiO2)
Quartz River Pebble with Algae
Silicon Dioxide (SiO2) with organic biofilm
Carnelian (Chalcedony)
Silicon Dioxide (SiO2)
Carnelian (Carnelian Agate)
Silicon Dioxide (SiO2) - variety of Chalcedony
Carnelian
Carnelian (Microcrystalline Quartz, SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous Phosphate of Copper and Aluminum)
Petrified Wood
Silicified wood (Quartz/Chalcedony)
Red Jasper
Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Yellow Jasper (with Iron staining)
Silicon Dioxide (SiO2)
Poppy Jasper
Jasper (variety of Chalcedony), SiO2 (Silicon Dioxide)
Chert (specifically Red Chert / Jasper nodule)
Silicon dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)
Jasper
Jasper (Silicon Dioxide, SiO2)
Red Jasper
Silicon Dioxide (SiO2) - variety of Chalcedony
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2 plus various impurities)
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
Jasper
Opaque Cryptocrystalline Quartz (SiO2)
Siltstone or Fine-grained Sandstone pebble
Siltstone (primarily SiO2 with clay minerals)
Jasper (specifically Brecciated or Agated Jasper)
Silicon Dioxide (SiO2) - Chalcedony with impurities
Opal
Hydrated silica (SiO2·nH2O)
Clear Quartz Crystal
Quartz (Silicon Dioxide - SiO2)
Chalcedony (Yellow Jasper or Agate)
Microcrystalline Quartz (SiO2)
Kyanite (Blue and Green varieties)
Kyanite (Al₂SiO₅)
Rough Precious Opal
Hydrated Silica (SiO2·nH2O)
Carnelian (Red Agate/Chalcedony)
Cryptocrystalline Quartz (SiO2) with Hematite impurities
Green Fluorite
Calcium fluoride (CaF2)
Jasper with Iron Staining
Silicon Dioxide (SiO2) with impurities
Magnetite
Magnetite (Fe3O4)
Calcite
Calcium Carbonate (CaCO3)
Brown Jasper
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Chert (Commonly known as Jasper or Flint)
Microcrystalline Quartz (SiO2)
Chert (often called Flint in dark varieties)
Microcrystalline or cryptocrystalline Quartz (SiO2)