Red Agate (Carnelian)
Silicon Dioxide (SiO2)
gemstone
Category
Mineral (Synthetic Paper And Ink Polymorph)
Browse mineral (synthetic paper and ink polymorph) specimens identified by the Rock Identifier community.
Learn about Mineral (Synthetic Paper And Ink Polymorph) in the encyclopedia
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Petoskey Stone (Fossilized Rugose Coral)
Hexagonaria percarinata
fossil
Chalk
Micrite (primarily Calcium Carbonate or CaCO3)
sedimentary
Petoskey Stone
Hexagonaria percarinata
sedimentary
Rose Quartz and Cherry Quartz (Dyed Glass/Quartz)
Silicon Dioxide (SiO2) with inclusions/dye
gemstone
Banded Agate (specifically shades of Carnelian Agate)
Silicon Dioxide (SiO2)
mineral
Amber
Succinite (Formula: C10H16O)
Mineraloid
Petoskey Stone
Hexagonaria percarinata
fossil
White Marble
Recrystallized Carbonate Rock (CaCO3)
metamorphic
Petoskey Stone
Hexagonaria percarinata
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Agate
Silicon Dioxide (SiO2) - Banded Chalcedony
mineral
Red faceted gemstone jewelry setting
Likely synthetic ruby or red spinel centerpiece with colorless accent stones; exact identification requires gemological testing
gemstone
Aragonite (variety 'Flos Ferri')
Aragonite (CaCO3)
Mineral
Ruby
Corundum (Al2O3)
gemstone
Diamond (or Diamond Simulant)
C (Carbon) or synthetic equivalent
gemstone
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossil Coral (Rugosa or Solitary Coral)
Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)
sedimentary
Polished pale stone, likely limestone or quartzite pebble
Most consistent with micritic limestone (calcite, CaCO₃), though the image cannot confirm mineralogy
sedimentary
Synthetic Resin / Plastic Figurine
Synthetic Polymer (Copolymer of Polyethylene or Resin)
Mineraloid-like Synthetic Material
Red gemstone ring, likely garnet or synthetic ruby
Possibly almandine garnet (Fe₃Al₂(SiO₄)₃) or corundum/ruby (Al₂O₃); image alone cannot distinguish
gemstone
Lapis Lazuli
Lazurite-dominated metamorphic rock ((Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)
metamorphic
Sandstone (Iron-stained)
Sandstone (dominated by Quartz, SiO2, with Iron Oxide impurities)
sedimentary
Chalk
Calcium Carbonate (CaCO3)
sedimentary
Orthoceras fossil in limestone
Orthoceras (extinct genus of cephalopod)
sedimentary
Orthoceras Fossil
Orthoceras regulare (Class Cephalopoda, Order Orthocerida)
fossil
Orange Moss Agate / Carnelian Agate
Silicon dioxide (SiO2) - variety Chalcedony
sedimentary
Kaolin Clay in Saprolite Profile
Kaolinite (Al2Si2O5(OH)4) within Weathered Pegmatite/Granite
sedimentary
Marble
Recrystallized Limestone (CaCO3)
metamorphic
Orthoceras Fossil in Limestone
Orthoceras regulare
sedimentary
Banded Iron Formation (BIF)
Banded Iron Formation (BIF)
sedimentary
Polished basalt with a quartz vein
Basalt, cut by milky quartz (SiO₂)
igneous
Ametrine
SiO2 (Silicon Dioxide with iron impurities)
gemstone
Graphite-bearing quartz-mica schist
Graphite-rich quartz–mica schist; primarily quartz (SiO₂), muscovite/biotite, and graphite (C)
metamorphic
Colorless Gemstone (possibly Diamond or Cubic Zirconia)
C (Diamond) or ZrO2 (Cubic Zirconia)
gemstone
Blue Sapphire (likely lab-grown or treated)
Corundum (Aluminum Oxide, Al2O3)
gemstone
Ruby (varietal of Corundum)
Corundum (Al2O3:Cr)
gemstone
Opalite
Man-made Opalized Glass (Synthetic Glass)
gemstone
Fossilized Brachiopod
Phylum Brachiopoda (General mineral composition: Calcite/CaCO₃ or Silica/SiO₂)
sedimentary
Blue Quartz / Glass Gemstone Pendant
SiO2 (Silicon Dioxide) or Synthetic Glass
gemstone
Amber
Succinite (specific to Baltic amber), fossilized tree resin
mineraloid
Cubic Zirconia (Set in Jewelry)
Zirconium Dioxide (ZrO2)
gemstone