Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2)
sedimentary
Category
Man Made Glass (Often Grouped With Minerals In Lapidary)
Browse man made glass (often grouped with minerals in lapidary) specimens identified by the Rock Identifier community.
Libyan Desert Glass
Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)
mineral (Tektite/Impactite)
Aura Quartz (Rainbow Quartz)
Silicon Dioxide (SiO2) with metallic vapor coatings
mineral
Dyed Aura Quartz
Silicon Dioxide (SiO2) with metallic coating
mineral
Transit Token (RTD Denver)
Nickel-plated brass or bronze alloy (Cu-Sn-Zn-Ni)
not a rock or mineral (anthropogenic material)
Carborundum
Silicon Carbide (SiC)
mineral
Goldstone
N/A (Synthetic Glass with Copper Inclusions)
Manufactured Glass
Orthoclase Feldspar (Sunstone variety)
KAlSi3O8 (Potassium Aluminum Silicate)
mineral
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
mineraloid
Aqua Aura Quartz
Silicon Dioxide (SiO2) bonded with Gold (Au)
mineral (treated)
Green Sea Glass
Amorphous Silica (man-made glass), SiO2 + additive metal oxides
mineraloid / anthropogenic (man-made origin)
Milky Quartz with Chlorite inclusion
Silicon Dioxide (SiO2) with Chlorite group inclusions
mineral
Porcelain (White Ceramic)
Mullite-bearing Vitrified Ceramic (Major phases: Mullite Al6Si2O13, Glassy Silica SiO2)
metamorphic
Asphalt (Bituminous Concrete)
Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)
not a rock (anthropogenic material/technofossil)
Metal Alloy (Likely Pewter or Sterling Silver)
Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).
Man-made material (metal)
Opalite
Man-made synthetic glass with opalescent effects (SiO2 + metal oxides)
mineraloid
Green Calcite
Calcite (CaCO3)
mineral
Concrete Fragment
Hardened Portland cement and mineral aggregate
sedimentary (anthropogenic)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Mother of Pearl (Nacre)
Aragonite (CaCO3) with Organic Matrix
mineral
Granodiorite
Granodiorite
Igneous
Pyrite Concretion (Grapestone)
Iron Sulfide (FeS2) Concretion
sedimentary
Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)
Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)
sedimentary
Aura Quartz (specifically Titanium Aura Quartz)
Titanium-coated Silicon Dioxide (SiO2 + Ti Coating)
mineral
Conglomerate
Conglomerate Rock (Paraconglomerate)
sedimentary
Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Milky Quartz with Chlorite inclusions
Silicon Dioxide (SiO2) with Chlorite group minerals
mineral
Carborundum (Silicon Carbide)
Silicon Carbide (SiC)
mineral
Dyed Imperial Jasper (Sea Sediment Jasper)
Silicon Dioxide (SiO2) - Impure Quartz/Chalcedony
sedimentary
Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Mineral
Goldstone (Brown)
Aventurine glass
mineraloid (man-made)
Stainless Steel (Polished)
Ferrous Alloy containing Iron (Fe), Chromium (Cr), and Carbon (C)
Mineral equivalent / Metal Alloy
Blue Crackle Quartz (Dyed Quarzite)
Silicon Dioxide (SiO2) with artificial dye
Metamorphic (modified)
Titanium Aura Quartz
Titanium bonded Silicon Dioxide (SiO2 + Ti)
mineral
Diamond
Native Carbon (C)
mineral
Chert (Nodule/Pebble)
Chert (Silicon Dioxide, SiO2)
sedimentary
Asphalt (Bituminous Pavement)
Bituminous mix (Aggregates with Bitumen binder)
sedimentary
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Man-made Object (Metal/Alloy)
Man-made Crystal (Lead Glass)
Lead oxide-doped Silica Glass (approx. SiO2 + PbO)
Mineraloid/Synthetic Material
Dyed Crackle Quartz
Silicon Dioxide (SiO2) with synthetic dye
mineral
Aura Quartz
Titanium or Gold bonded Silicon Dioxide (SiO2)
mineral