Obsidian
Volcanic Glass (SiO2)
igneous
Category
Mineraloid (Synthetic)
Browse mineraloid (synthetic) specimens identified by the Rock Identifier community.
Garden Quartz (Lodalite)
Silicon Dioxide with various mineral inclusions (SiO2)
mineral
Painted River Rock
Anthropogenic-modified Siliciclastic Sedimentary Rock
Sedimentary
Silicon Carbide (Carborundum)
Silicon Carbide (SiC)
mineral
Amber with Inclusion
Succiniferous fossil resin (C10H16O)
mineraloid
Emerald in Matrix
Beryl (Be3Al2Si6O18) with trace amounts of Chromium/Vanadium
mineral
Man-made Jewelry Charm (Enameled Metal)
Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.
Synthetic / Manufactured Artifact
Assorted Semi-Precious Gemstone Crosses
Quartz, Silicates, Carbonates (various)
mineral
Mahogany Obsidian
Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)
igneous
Obsidian
Obsidian (volcanic glass), primarily SiO2 (silicon dioxide)
igneous
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions (70–75% SiO2)
Igneous
Obsidian
Amorphous volcanic glass (primarily SiO2)
igneous
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
igneous
Obsidian
Obsidian (Volcanic Glass)
igneous
Limonite (Iron Stone/Ocher)
Limonite (FeO(OH)·nH2O)
mineral
Obsidian
Volcanic glass (mainly SiO2 with inclusions)
igneous
Limonite/Goethite on Shale
Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock
sedimentary
Blue Goldstone
Synthetic Avanturine Glass (or Aventurine Glass)
Synthetic Glass
Blue Cracked Quartz (Dyed Fire Crackle Quartz)
Silicon Dioxide (SiO2) with synthetic dye
mineral
Lava Stone and Chakra Beads
Basalt (with various mineral/synthetic beads)
igneous
K2 Stone (or K2 Jasper)
Azurite-in-Granite (Potassium Feldspar, Quartz, Plagioclase, Muscovite, and Azurite)
igneous
Dyed Agate
Silicon Dioxide (SiO2) - variety Chalcedony
mineral
Black Obsidian
Volcanic Glass (SiO2 + impurities like Fe3O4)
igneous
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
igneous
Snowflake Obsidian
Hydrated Volcanic Glass (primarily SiO2) with Cristobalite inclusions
igneous
Amber
Amber (C10H16O)
mineral
Obsidian
Volcanic Glass (SiO2)
igneous
Opal
Hydrated amorphous silica (SiO2·nH2O)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Blue Sapphire
Corundum (Al2O3)
mineral
Ruby (Rough/Raw)
Corundum (Al2O3:Cr)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Amber (Black)
Amber (succinite, retinite, etc., specifically, heavily included/dark varieties)
Mineraloid
Ruby (Pink to Red Corundum)
Al2O3 (Corundum with Chromium impurities)
mineral
Ruby
Corundum (Al2O3 with Chromium traces)
mineral
Blue Sapphire
Corundum (Al2O3)
mineral
Black Pearl (Tahitian Pearl)
Aragonite / Calcite (CaCO3) with Conchiolin
mineral
Cubic Zirconia (Man-made)
Cubic Zirconia (ZrO2) with Enamel and Metal Alloy
mineral
Asphalt (Bituminous Concrete)
Bituminous mix / Anthropogenic conglomerate
man-made composite (lithified equivalent of sedimentary)
Pearl
Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3
mineral
Acrylic or Resin (Synthetic Imitation)
Polymethyl Methacrylate (PMMA) or Polyepoxide
Synthetic/Man-made Polymer
Obsidian
Volcanic Glass (70-75% SiO2)
igneous