Amethyst
Silicon Dioxide (SiO2)
mineral
Category
Man Made Byproduct (Often Mistaken For Obsidian Or Emerald)
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Learn about Man Made Byproduct (Often Mistaken For Obsidian Or Emerald) in the encyclopedia
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Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Quartzite
Metamorphic Quartz Rock (SiO2)
metamorphic
Quartzite (Iron-stained)
Quartzite (SiO2 with iron oxides)
metamorphic
Jasper with Dendritic Inclusions
Microcrystalline Quartz (SiO2) with manganese or iron oxide inclusions
sedimentary
Black Onyx
Silicon Dioxide (SiO2) with parallel banding
mineral
Malachite-bearing copper ore
Malachite, Cu₂CO₃(OH)₂, likely mixed with chrysocolla, copper minerals, and iron oxides
mineral
Quartzite with Dendritic Manganese Oxide Inclusions
Metamorphic Quartzite (SiO2 with Mn-oxides)
metamorphic
Yellow Jasper with Dendritic Inclusions
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
sedimentary
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Olivine in Basalt (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4 (Mineral) within Basalt (Rock)
igneous
Ironstone Concretion
Limonitic/Hematitic Concretion
sedimentary
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Gypsum (Satin Spar / Alabaster variety)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
mineral
Iron Slag (Industrial Byproduct)
Anthropogenic pyrometallurgical residue
mineral
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
sedimentary
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
metamorphic
Yellow Calcite
Calcium Carbonate (CaCO3)
mineral
Quartzite
Metamorphic Quartz Rock (SiO2)
metamorphic
Eclogite
Eclogite (Omphacite + Almandine-Pyrope Garnet)
metamorphic
Red Quartzite
Quartzite (Metamorphosed Quartz Arenite)
metamorphic
Chert (often called Flint in archaeological contexts)
Microcrystalline or cryptocrystalline Silica (SiO2)
sedimentary
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous
Milky Quartz with Dendritic Inclusions
Silicon Dioxide (SiO2) with impurities
mineral
Lepidodendron Fossil (Scale Tree)
Lepidodendron sp.
fossil
Sulfur
Native Sulfur (S)
mineral
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Dendritic sandstone
Sandstone with Manganese Oxide dendrites
sedimentary
Manganese Dendrite on Siltstone
Manganese Oxide (pyrolusite or psilomelane) Dendrites
mineral/sedimentary
Quartzite
Metamorphic Quartzite (primarily SiO2)
metamorphic
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Quartzite
Metamorphic Quartzite (primarily SiO2)
metamorphic
Dendrite (Manganese Oxide Dendrites)
Psilomelane or Pyrolusite on Matrix (typically MnO2)
mineral
Sandstone with Dendritic Inclusions
Quartzose Sandstone
sedimentary
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Quartzite
Metamorphic Quartzite (SiO2)
metamorphic
Quartzite (Lithic Artifact)
Quartzite (SiO2)
metamorphic
Coal (Bituminous Coal)
Caustobiolith / Sedimentary Rock
sedimentary