Druzy Quartz on Vesicular Basalt
Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock
Category
Browse organic gemstone specimens identified by the Rock Identifier community.
Druzy Quartz on Vesicular Basalt
Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock
Fossiliferous Chert (with Fossil Shells)
Silicon Dioxide (SiO2) with biogenic inclusions
Limonite (Iron Ore)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Travertine
Calcareous Tufa / Travertine (CaCO3)
Petrified Wood
Silicified Wood (primarily SiO2)
Cardstock (Paper)
Cellulose (C6H10O5)n
Petrified Wood
Silicified Wood (SiO2 permineralization)
Fossil Shell Fragment (possibly Brachiopod or Bivalve)
Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca
Human Skin (Epidermis/Dermis)
Integumentary tissue (High content of hydroxyapatite in bones, though the surface is biological)
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Limestone with Bitumen/Chert
Calcite (CaCO3) containing organic hydrocarbons
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of Cellulose)
Petrified Wood
Silicified Wood (SiO2)
Fossiliferous Limestone
Bioclastic Limestone (composition: CaCO3)
Chert
Chert (Microcrystalline Quartz, SiO2)
Mother of Pearl (Nacre)
Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Hand-Drawn Trading Card (Amateur Artwork)
Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)
Sandstone with Algae Growth
Arenite with Chlorophyta/Lichen
Chert / Chalcedony
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (varieties: Flint, Jasper)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (often called Flint)
Chert (SiO2)
Chert (Nodule)
Chert (Cryptocrystalline Silica, SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert with Quartz Vein
Silicon dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Fairy Stone (Menilite Concretion)
Carbonate-rich concretion (often Siderite or Calcite in Clay)
Glauconitic Sandstone
Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (Nodule/Common Chert)
Microcrystalline quartz (SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert
Silicon dioxide (SiO2)
Chert (Flint Pebbles)
Microcrystalline Quartz (SiO2)