Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Category
Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.
Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Jasper
Silicon Dioxide (SiO2) with impurities
Chert (Yellow/Tan)
Microcrystalline Quartz (SiO2)
Chert (Smooth River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Opaline Silica (SiO2)
Unidentified Rock Fragment
Unknown
Chert (Jasper/Jasperoid)
Chert (chemically precipitated microcrystalline Quartz, SiO2)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Red Jasper
Quartz (SiO2) with iron oxide inclusions
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Yellow Jasper / Chert
Jasper (Silica/Quartz) - SiO2
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Vesicular basalt (scoriaceous volcanic rock)
Basalt, chiefly plagioclase, pyroxene, and commonly olivine; vesicles may be lined with secondary minerals
Red Chert (Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Pearl
Calcium Carbonate (Aragonite/Calcite) with Conchiolin
Chert
Microcrystalline Quartz (SiO2)
Chondrite Meteorite
Ordinary Chondrite (Undifferentiated Stony Meteorite)
Chondrite Meteorite
Stony Meteorite (Ordinary Chondrite)
Baltic Amber
Succinite (Fossilized Resin)
Petrified Wood
Silicified Wood (SiO2)
Chert (Black Chert/Flint)
Silicon Dioxide (SiO2)
Fossil bivalve shell
Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Green variety)
Silicon Dioxide (SiO2)
Chert (specifically Flint)
Silicon Dioxide (SiO2)
Jasper
Jasper (Silicon Dioxide) - SiO2
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
White Coral
Corallium rubrum (biocarbonate calcium) / CaCO3
Chert (Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (often called Flint or Agate nodule)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Chalcedony)
Microcrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Amber (Raw Copal)
Fossilized Plant Resin (Gummite/Succinite)
Chert (Blue-Gray Chert)
Microcrystalline quartz (SiO2)
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2) / Microcrystalline Quartz
Petrified Wood
Silicified Wood (SiO2)
Polished banded agate (likely picture jasper or petrified wood)
Microcrystalline quartz, SiO₂, with iron-oxide and clay inclusions
Red Chert (Jasper)
Cryptocrystalline Quartz (SiO2) with iron oxide inclusions
Jasper
Jasper (Cryptocrystalline variety of Quartz, SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides