Fluorite
Calcium Fluoride (CaF2)
Category
Browse mineraloid (synthetic) specimens identified by the Rock Identifier community.
Fluorite
Calcium Fluoride (CaF2)
Staurolite (Fairy Stone)
Staurolite (Fe2+2Al9Si4O23(OH))
Ruby
Corundum (Al2O3 with Chromium impurities)
Malachite
Cu2CO3(OH)2 (Copper Hydroxide Carbonate)
Blue gemstone ring, likely lapis lazuli
Lapis lazuli: lazurite-rich metamorphic rock, chiefly (Na,Ca)8(AlSiO4)6(S,SO)2, commonly with calcite and pyrite
Amethyst cabochon ring
Amethyst, purple quartz (SiO₂)
Amethyst jewelry centerpiece
Amethyst, purple quartz (SiO₂), likely set with colorless diamonds or other gems
Banded Black Onyx (Chalcedony)
Silicon Dioxide (SiO₂)
Obsidian
Volcanic glass (Amorphous silicon dioxide)
Obsidian
Volcanic glass
Mahogany Obsidian
Volcanic Glass (SiO2 with Fe/Mg oxides)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Opalite (Man-made Glass)
Synthetic Silicon Dioxide Glass (SiO2 + metal oxides)
Faceted clear gemstone, likely quartz or glass imitation
Most likely quartz (SiO₂); exact identification requires refractive-index and hardness tests
Goldstone
Avventurina (Man-made Glass with Copper inclusions)
Silicon Carbide (Carborundum)
Silicon Carbide (SiC)
Silicon
Element Si
Opalite
Man-made Synthetic Glass (Silicon Dioxide with metal additives)
Yellow-orange amber
Fossilized tree resin; amber is an organic mineraloid, not a true mineral
Amber (polished piece)
Fossilized tree resin; amber is an organic mineraloid, not a true mineral
Yellow amber beads
Amber (fossilized tree resin; organic mineraloid, not a true mineral)
Polished amber inclusion specimen
Amber (fossilized plant resin), commonly succinite; organic mineraloid
Common Opal (Potch)
Hydrated Silica (SiO2·nH2O)
Black Obsidian
Volcanic glass (Amorphous silicates)
Limonite with Quartz (Gossan)
Hydrated iron(III) oxide-hydroxide mixture (FeO(OH)·nH2O) with Silicon Dioxide (SiO2)
White Opal (Common)
Hydrated Silica (SiO2·nH2O)
Blue Agate Geode (Dyed)
Cryptocrystalline Quartz (SiO2)
Tumbled amber
Amber (fossilized plant resin), commonly succinite; organic mineraloid
Amber-bearing rough specimen
Fossilized plant resin (amber; organic mineraloid), commonly succinite
Small yellow-orange mineral fragment, likely amber or iron-stained quartz
Possibly amber (fossilized resin; organic mineraloid) or quartz (SiO₂)
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Diamond (or high-quality simulant like Cubic Zirconia)
Carbon (C) - Native Element
Green glassy cabochon, likely dyed or synthetic material
Uncertain; possibly green obsidian, chrysoprase, or synthetic glass
Polished labradorite cabochon
Labradorite, calcium-rich plagioclase feldspar; approximately (Ca,Na)(Al,Si)₄O₈
Ruby
Corundum (Al2O3 with Chromium traces)
Emerald
Beryl, Be₃Al₂(SiO₃)₆, colored green mainly by chromium and/or vanadium
Acrylic or Resin (Synthetic Imitation)
Polymethyl Methacrylate (PMMA) or Polyepoxide
Agate (Polished Sphere)
Silicon Dioxide (SiO2)
Diamond
Diamond (C)
Turquoise cabochon pendant
Turquoise, hydrated copper aluminum phosphate — CuAl₆(PO₄)₄(OH)₈·4H₂O
Faceted quartz crystal sphere (likely rock crystal)
Quartz, silicon dioxide (SiO₂)
Tumbled turquoise cabochon
Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O