Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
Category
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
Chert (and associated Sedimentary rocks)
Microcrystalline Silica (SiO2)
Jasper (Iron Oxide Rich)
Silicon Dioxide (SiO2) with Fe2O3 (Hematite/Goethite) inclusions
Chrysocolla Chalcedony
Hydrated Copper Phyllosilicate (Cu,Al)2H2Si2O5(OH)4 + SiO2
Precious Red Coral
Corallium rubrum (Calcium Carbonate, CaCO3)
Sandstone with Algae Growth
Arenite with Chlorophyta/Lichen
Red Shale
Fissile Siliciclastic Sedimentary Rock
Amber
Succinicum (Organic Gemstone - Resinite)
Green Jasper
Silicon Dioxide (SiO2) with mineral inclusions
Golden Mica Schist
Mica Schist (primarily Muscovite/Biotite with Quartz)
Jasper with Quartz Veining
Silicon Dioxide (SiO2) with impurities such as Fe2O3
Green Agate
Silicon dioxide (SiO₂)
Ferruginous Sandstone (with possible trace fossils)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)
Chert (Fossiliferous)
Silicon dioxide (SiO2)
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
Sugilite
Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)
Malachite
Malachite (Copper Carbonate Hydroxide, Cu2CO3(OH)2)
Amazonite
Triklinic Potassium Feldspar (KAlSi3O8)
Chert (Flint)
Silicon Dioxide (SiO2)
Amber (Dark/Black Variety)
Succinite (Resinite), C10H16O
Chert (Arrowhead Debitage or Spall)
Silicon Dioxide (SiO₂)
Chert / Chalcedony
Silicon Dioxide (SiO2)
Yellow Jasper (Chert)
Silicon Dioxide (SiO2) with iron inclusions
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert / Flint Nodules
Chert (Cryptocrystalline variety of Quartz, SiO2)
Psilomelane (Manganese Ore)
Psilomelane (Ba,H2O)2Mn5O10
Blue Chalcedony
Silicon Dioxide (SiO2)
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate) - (Mn,Fe,Mg,Ca)SiO3
Chert (containing Iron Oxide)
Microcrystalline Quartz (SiO2)
Apatite
Apatite group mineral (e.g., Fluorapatite - Ca5(PO4)3F, Chlorapatite - Ca5(PO4)3Cl, Hydroxylapatite - Ca5(PO4)3(OH))
Milky Quartz Vein with Matrix
Silicon Dioxide (SiO2)
Yellow Calcite
Calcium Carbonate (CaCO3)
Chert (Dark Variety / Flint)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
Petrified Wood
Silicified Wood (primarily SiO2)
Moss Agate and Hematite
Silica (SiO2) with fibrous inclusions of Manganese or Iron; Hematite (Fe2O3)
Chert (Smooth River Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (with Limestone matrix)
Silicon dioxide (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Micro-crystalline Quartz Pebble (Chert)
Silicon dioxide (SiO2)