Abalone Shell (Nacre)
Aragonite (CaCO3) - Biogenic Mineral
mineral
Category
Mineraloid (Man Made Glass)
Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.
Learn about Mineraloid (Man Made Glass) in the encyclopedia
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Goldstone and pink quartz bead strands
Goldstone is aventurescent copper-bearing glass; pink beads are likely rose quartz (SiO₂), though dyed or glass imitations are possible
mineral
Native Silver
Silver (elemental Ag)
mineral
Amber in Matrix
Succinite (Carbon-based organic polymer)
Organic (Sedimentary context)
Nickel coin (U.S. currency)
Cupronickel (75% Copper, 25% Nickel alloy)
man-made alloy (metallic)
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
igneous
Obsidian
Volcanic glass
igneous
Green Aventurine
Silicon Dioxide (SiO2+KAl2(AlSi3O10)(OH)2)
metamorphic
Limonite (Iron Ore)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
mineral
Jet
Lignite (Anthracite-grade compact coal)
sedimentary
N/A - Man-made object (Jewelry Chain)
Antiqued or Oxidized Metal Chain (often Steel or Brass)
Mineral (processed metal)
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
Chert
Microcrystalline Quartz (SiO2)
sedimentary
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
metamorphic (man-made / anthropic)
Precious Opal
Hydrated Silica (SiO2·nH2O)
mineral
Limonite/Ironstone
Limonite (FeO(OH)·nH2O)
mineral
Chert
Chert (Microcrystalline Quartz)
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Pearl
Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3
mineral
Green Opal
Hydrated Silica (SiO2·nH2O)
mineraloid
Rough Sapphire (Corundum)
Corundum (Al2O3)
mineral
Opal (in Jewelry Setting)
Hydrated Silicon Dioxide (SiO2·nH2O)
gemstone
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Diamond (in a gold ring)
Diamond (pure carbon, C)
mineral
Man-made Green Quartz (Lab-grown or Treated)
Silicon Dioxide (SiO2) with artificial coloration
mineral
Obsidian
Volcanic glass (SiO2)
igneous
Pearl and Garnet Glass
Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass
mineral and glass
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
igneous
Opal
Hydrated Silica (SiO2·nH2O)
mineral
Limonite (Ironstone)
Limonite (mixture of hydrated iron(III) oxide-hydroxides)
mineral
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
igneous
Opal
Hydrated silica (SiO2 "NH2O)
mineraloid
Amber
Amber (C10H16O)
mineral
Opal
Hydrated amorphous silica (SiO2·nH2O)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)
mineral
Luminous Stone (Glow-in-the-dark Synthetic/Man-made Stone)
Strontium Aluminate tinted glass or resin (Crystalline silicate/oxide mix)
mineral (synthetic)
Diamond
Carbon (C)
gemstone
Flint
SiO2 (Cryptocrystalline Quartz)
sedimentary
Green Slag Glass
Cullet (Amorphous Silicon Dioxide with impurities)
Man-made rock-like material
Slag
Ferrous slag (by-product of iron smelting)
Mineraloid / Anthropogenic
Chert (Flint / Quartz Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Chert or Jasper
Microcrystalline Quartz (SiO2)
sedimentary