Quartz with Mica inclusions (Pegmatite)
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
igneous
Category
Industrial Byproduct (Often Mistaken For Obsidian Or Mineral)
Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.
Amethyst and Limestone
Amethyst (SiO2 - Silicon Dioxide) and Limestone (CaCO3 - Calcium Carbonate)
The purple specimen is a mineral (Amethyst); the white specimen is a sedimentary rock (Limestone or Marble).
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Ruby
Corundum (Al2O3 with Chromium impurities)
mineral
Limonite (Iron Ore)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
mineral
Sandstone (with Limonite staining)
Arenite (primarily SiO2 with FeO(OH)·nH2O)
sedimentary
Epidote
Epidote - Ca2(Al,Fe)3(SiO4)3(OH)
metamorphic
Pyrite with Calcite
Iron Disulfide (FeS2) with Calcium Carbonate (CaCO3)
mineral
Limonite
Limonite (Hydrous iron oxides, FeO(OH)·nH2O)
mineral
Gold in Matrix
Native Gold (Au)
mineral
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Ruby in Kyanite
Corundum in Disthene (Al2SiO5 + Al2O3)
metamorphic
Note: Image shows a biological specimen (Rat), not a rock. Representative geological equivalent: Galena (due to lead-grey colors in fur).
Galena (PbS)
mineral
Lepidolite with Quartz
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Gneiss (likely)
Gneiss
Metamorphic
Sodalite
Sodalite (Na4Al3Si3O12Cl)
Mineral
Greenstone
Metabasalt / Chlorite-Epidote Schist
metamorphic
Lepidolite in Quartz
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 / SiO2
mineral
Chalcedony on Matrix
Silicon Dioxide (SiO2)
mineral
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
mineral
Greenstone / Epidosite
Epidosite (Metasomatic rock consisting mainly of Epidite Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH) and Quartz)
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Demitasse Granite (Diorite-Granite transition)
Intermediate Plutonic Rock (Granodiorite/Diorite mix)
igneous
Nobby Hematite (Iron Ore)
Hematite (Fe2O3)
mineral
Chalcedony (variations like Agate or Jasper)
Chalcedony (SiO₂ - microcrystalline quartz)
Mineral
Ferruginous Quartz
Quartz (Silicon Dioxide) - SiO2 with Iron Oxide inclusions
mineral
Green Jasper with Quartz veins
Jasper (Silicon Dioxide, SiO2)
sedimentary
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Limonite (Hydrated Iron Oxide / Bog Iron)
FeO(OH)·nH2O
Mineral (Sedimentary context)
Pyrite (Iron Pyrites)
Iron Sulfide (FeS2)
mineral
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Mineral
Satin Spar (Gypsum)
Hydrous Calcium Sulfate (CaSO4·2H2O)
mineral
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Satin Spar (Gypsum)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
mineral
Schist
N/A (a rock type, not a mineral formula)
metamorphic
Rough Quartz (Milky Quartz Pebbles)
Silicon Dioxide (SiO2)
mineral
Gneiss
Foliated Metamorphic Rock (Gneiss)
metamorphic
Gossan (Iron Hat)
Limonitic Gossan (predominantly FeO(OH)·nH2O)
igneous/metamorphic derivative