Dzi Bead (Etched Chalcedony)
Cryptocrystalline Quartz (SiO2) with chemical etching
Category
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Dzi Bead (Etched Chalcedony)
Cryptocrystalline Quartz (SiO2) with chemical etching
Fuchsite (Green Muscovite)
K(Al,Cr)2(AlSi3O10)(OH)2
Obsidian (worked into an arrowhead profile)
Obsidian (volcanic glass), primarily SiO2 (Silicon Dioxide)
Dendritic Siltstone (or Mudstone)
Siltstone with Manganese Oxide dendrites
Peridot (likely, given the color and bead form)
Olivine, variety Peridot (Mg,Fe)2SiO4
Slag (Industrial Glass/Byproduct)
Anthropogenic Vitreous Silicate
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Smoky Quartz (Tumbled)
Silicon Dioxide (SiO2)
Dalmatian Stone
Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)
Fluorite (likely Green Fluorite variant)
Calcium Fluoride (CaF2)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Fuchsite Gneiss (Green Quartzite)
Chromium-rich Muscovite (KAl2(AlSi3O10)(OH)2 with Cr replacements)
Fuchsite in Quartz
K(Al,Cr)2(AlSi3O10)(OH)2 (Muscovite with Chromium)
Granite
Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).
Blue Cracked Quartz (Dyed Fire Crackle Quartz)
Silicon Dioxide (SiO2) with synthetic dye
Emerald In Matrix (Quartz/Calcite)
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
Silicon Carbide (Carborundum)
Silicon Carbide (SiC) / Moissanite (natural)
Pearl
Aragonite (CaCO3 with conchiolin)
Unidentifiable Rock Fragment
Rough Diamond
Pure Carbon (C)
Amethyst (Geode)
Silicon Dioxide (SiO2) with iron impurities
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Jadeite
NaAlSi2O6 (Sodium Aluminum Silicate)
Obsidian
Volcanic Glass (predominantly SiO2 – Silicon Dioxide, but non-crystalline)
Dendritic Opal
Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
Obsidian
Volcanic Glass (SiO2 + impurities)
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Dyed Agate / Painted Stone
Silicon Dioxide (SiO2) with artificial pigment
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Aquamarine
Beryl (Be3Al2Si6O18 with iron impurities)
Fuchsite (Chrome Mica)
K(Al,Cr)2(AlSi3O10)(OH)2
Ceramic or Polished Stone Heart (Anthropogenic Material)
Glazed Ceramic (Silicon Dioxide based coating on Alumina Silicate body) or Polished Limestone/Marble (Calcium Carbonate, CaCO3)
Opalite
Synthetic Fluorescent Glass (SiO2 + impurities)
Cultured Marble (Synthetic)
Polymer-matrix composite (typically calcium carbonate in polyester resin)
Libyan Desert Glass
Tektite (high-silica impact glass), SiO2
Aquamarine with Ruby Accent
Beryllium Aluminum Silicate (Be3Al2Si6O18) with Aluminum Oxide (Al2O3)
Kyanite (Green and Blue varieties)
Kyanite (Al2SiO5)
Sandstone (likely Fossiliferous)
Arenite / Fossiliferous Sandstone (SiO2 composition)
Peridot (Olivine)
Olivine, (Mg,Fe)2SiO4
Titanium-coated Metal Cube (Man-made Fidget Toy)
Titanium-anodized or electroplated alloy (e.g., Ti-coated Zinc or Aluminum)
Alexandrite in Matrix
Chrysoberyl (BeAl2O4 with Chromium impurities)
Synthetic Resin / Plastic Figurine
Synthetic Polymer (Copolymer of Polyethylene or Resin)