Ruby in Matrix
Corundum (Al2O3)
Category
Browse organic gem material (botanical) specimens identified by the Rock Identifier community.
Ruby in Matrix
Corundum (Al2O3)
Pearl (Imitation or Cultured)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)
Chert (Jasper)
Microcrystalline quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (varietal: Flint/Jasper)
Silicon Dioxide (SiO2)
Sandstone (River Cobble)
Clastic sedimentary rock (primarily SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Rhodonite
(Mn,Fe,Mg,Ca)SiO3
Petrified Wood
Silicified wood (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Limonite (Iron Ore)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Red Jasper with Quartz
Microcrystalline Quartz (SiO2)
Dinosaur Fossil Tooth
Vertebrate Fossilized Tooth
Fossil Shark Tooth
Selachii (fossilized dentition)
Bivalve Fossil (Fossilized Shell)
Class Bivalvia (fossilized in Calcium Carbonate/Aragonite)
Fossil Coral
Scleractinia or Anthozoa (Fossilized)
Ironstone Concretion
Ironstone (primarily Siderite or Limonite)
Petrified Wood
Silicified Wood (primarily SiO2)
Yellow Chert (Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Tumbled epidote or epidote-rich stone
Epidote, Ca₂(Al,Fe)₃(SiO₄)₃(OH); possibly a green jasper or prehnite-epidote aggregate
Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (Concretion or Nodular Variety)
Microcrystalline Quartz (SiO2)
Copper ore-bearing rock (likely malachite/chrysocolla in a sulfide-rich matrix)
Cuprite–malachite/chrysocolla mineralization; probable copper sulfides such as chalcopyrite in altered host rock
Chert (specifically Cryptocrystalline Quartz)
Silicon dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Clear quartz crystal
Quartz (silicon dioxide, SiO₂)
Mixed collection of natural stones
Several unidentified lithologies, likely including basalt, granite, quartzite, sandstone, and weathered metamorphic rocks
Chert or flint fragment
Microcrystalline quartz (SiO₂), likely iron-stained chert
Petrified Wood
Silicified Wood (SiO2)