Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Category
Browse man made silicate (anthropogenic glass) specimens identified by the Rock Identifier community.
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Chert / Flint
Chert (Microcrystalline Quartz, SiO2)
Kunzite (variety of Spodumene)
Lithium Aluminum Silicate (LiAlSi2O6)
Chert (variant Flint/Jasper)
Microcrystalline Opaline Silica (SiO2)
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide staining)
Agate (or Banded Agate)
Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)
Jasper (specifically Oolitic or Brecciated Jasper)
Silicon Dioxide (SiO₂)
Serpentinite
Serpentinite (complex silicate of magnesium, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)
Quartz (milky quartz variety)
Quartz (SiO₂)
Quartzite
Quartzite (primarily SiO2)
Amethyst
Quartz (SiO2) with trace iron impurities
Quartzite
Quartzite (primarily SiO2)
Osumilite in Granite Matrix
(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30
Mixed Gemstone Beaded Jewelry
Various minerals (e.g., Quartz varieties like Rose Quartz, Amethyst; Peridot; Garnet; etc.)
Snowflake Obsidian
Volcanic glass with Spherulite inclusions (SiO2)
Fulgurite
Fulgurite (Lechatelierite)
Snowflake Obsidian
Spherulitic Obsidian (SiO2 + impurities)
Snowflake Obsidian
Volcanic glass containing Spherulites (SiO2)
Cavansite
Cavansite (Ca(VO)Si4O10·4H2O)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Morganite (Pink Beryl)
Beryllium aluminum silicate Be3Al2(SiO3)6
Serpentinite
Serpentinite (complex silicate minerals including Mg3Si2O5(OH)4)
Banded Gneiss
Gneiss (pronounced 'nice')
Obsidian with Mahogany Phasing
Volcanic Glass (SiO2 + Fe2O3)
Obsidian
Volcanic glass (SiO2-rich extrusive igneous rock)
Ferruginous Quartz
Iron-stained Quartz (SiO2 with Fe2O3 impurities)
Jasper with Epidote
Silicon Dioxide (SiO2) with Calcium Aluminum Iron Sorosilicate [Ca2Al2Fe3+Si3O12(OH)]
Banded Calcite (often commercially sold as 'Mexican Onyx' or 'Honey Onyx')
Calcite (Calcium Carbonate, CaCO3)
Green Jasper with Agate Banding
Silicon Dioxide (SiO2) with impurities of ferrous silicate or chlorite
Quartz Druzy (on Matrix)
Silicon Dioxide (SiO2)
Quartzite Pebble
Quartzite (mostly SiO2)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Limonite with Opal infusion
FeO(OH)·nH2O (Limonite) / SiO2·nH2O (Opal)
Anthracite Coal
Anthracite (Carbon-rich metamorphic rock)
Chert (Gravel)
Silicon Dioxide (SiO2)
Pyrite on Quartz
Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2)
Obsidian
Obsidian (volcanic glass), amorphous SiO2 + impurities
Obsidian
Obsidian (Amorphous Volcanic Glass, SiO2)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions (70–75% SiO2)
Pumice
Pumice (Vesicular volcanic glass)
Basalt with Iron Oxidation
Amygdaloidal Basalt (silicate rock primarily plagioclase, pyroxene, and olivine)