Chert (Siliceous Mudstone variant)
Microcrystalline quartz (SiO2)
Category
Browse mineral, organic gemstone specimens identified by the Rock Identifier community.
Chert (Siliceous Mudstone variant)
Microcrystalline quartz (SiO2)
Chert (Nodular)
Microcrystalline Silica (SiO2)
Amber
Succinite (a variety of fossilized tree resin); chemical formula appx. C10H16O
Chert
Chert (Microcrystalline Quartz, SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (with Quartz Druzy)
Microcrystalline Silica (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron inclusions
Chert / Flint
Silicon dioxide (SiO2)
Cultured pearls
Pearl; predominantly aragonite (CaCO₃) in nacre with organic conchiolin
Amber
Succinate (Fossilized Resin)
White limestone or chalky carbonate rock
Calcite-rich limestone; possibly chalk (CaCO₃)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Green Chert (Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Small yellow-orange mineral fragment, likely amber or iron-stained quartz
Possibly amber (fossilized resin; organic mineraloid) or quartz (SiO₂)
Sandstone
Arenite
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Pink Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Chert
Microcrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Translucent amber-colored gemstone, likely citrine or amber
Most plausibly quartz (SiO₂), specifically citrine; amber would be fossilized resin (organic polymer)
Jasper
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Jasper variety)
Silicon Dioxide (SiO2) with iron oxide impurities
Chert (Smooth River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (SiO2)
Chert (often called Flint)
Chert (Cryptocrystalline Silica, SiO2)
Chert (often called Flint when found in chalk)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Gravel / Limestone Fragment
Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock
Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Amber
Succinates (Organic Fossilized Resin)
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Petrified Wood / Fossilized Bone
Silicified / Mineralized Fossil (Silica SiO2)
Amber
Fossilized Tree Resin (Successite)
Fossilized Shark Tooth
Selachimorpha fossil
Petrified Bone (Fossil Bone)
Per mineralization fossil bone (varies by organism, predominantly replacement by SiO2 - Quartz/Chalcedony)
Jasper (Red Jasper)
Silicon Dioxide (SiO₂)