Dumortierite Quartz
Dumortierite in Quartz (Al6O3(BO3)(SiO4)3)
mineral
Category
Sedimentary (Processed Mineral Product)
Browse sedimentary (processed mineral product) specimens identified by the Rock Identifier community.
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Milky Quartz with Chlorite / Mica inclusions
Silicon Dioxide (SiO2) with phyllosilicate inclusions
igneous
Hematite
Iron(III) oxide (Fe2O3)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Blue Kyanite
Kyanite (Al2SiO5)
mineral
Colorless quartz crystal (likely quartz fragment)
Quartz, silicon dioxide (SiO₂)
mineral
Hematite bead bracelet
Hematite (Fe₂O₃), likely polished or magnetically enhanced beads
mineral
Pumice
Pumice (extrusive volcanic rock)
igneous
Dyed Fuchsia Tiger’s Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Blue Impression Jasper beads
Impression jasper (microcrystalline quartz/chalcedony), chiefly SiO₂, with iron-oxide and other mineral inclusions
gemstone
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pyrite (likely)
Iron disulfide, FeS₂; commonly called fool’s gold
mineral
Opalite
Man-made glass (traditionally simulated Opal)
mineral
Weathered iron-rich rock, possibly laterite or limonite-bearing sandstone
Iron oxides/hydroxides, chiefly limonite/goethite (FeO(OH)·nH₂O), with a probable silicate or clay matrix
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Fluorite (Rainbow Fluorite)
Calcium Fluoride (CaF2)
mineral
Gossan (Iron Hat)
Gossan (secondary iron oxide cap)
sedimentary
Hematite
Hematite (Fe2O3)
mineral
Granite Gneiss
Gneiss (High-grade Metamorphic Rock)
metamorphic
Iron-stained weathered pebble
Likely ferruginous sandstone or iron-rich chert; exact identification requires testing
sedimentary
Heat-Treated Citrine (Amethyst-based)
Quartz (Silicon Dioxide) - SiO2
mineral
Tumbled Hematite
Iron(III) oxide (Fe2O3)
mineral
Red Shale
Lutite (primarily composed of Hydrous Aluminum Silicates with Hematite staining)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Yellow Ochre / Limonite
FeO(OH)·nH2O (Hydrated Iron Oxide Mix)
mineral
Epidote
Ca2(Al,Fe)3(SiO4)3(OH)
mineral
Dead Sea Salt Crust
Halite (NaCl)
sedimentary
Blue Kyanite
Kyanite (Al2SiO5)
mineral
Crushed Granite and Quartz Gravel
Composite Igneous and Silicate Rock Aggregate
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Tumbled green-yellow chalcedony (likely prehnite or serpentine)
Cryptocrystalline quartz (chalcedony), SiO₂; identification is uncertain from the photograph
mineral
Blue calcite (likely)
Calcite, calcium carbonate (CaCO₃)
mineral
Chalcedony (Yellow Agate)
Cryptocrystalline Quartz (SiO2)
mineral
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
sedimentary
Tumbled lavender quartz (likely lepidolite-bearing quartz or dyed quartz)
Quartz, SiO₂; possible lepidolite mica inclusions
mineral
Quartz (Tumbled/Water-worn)
Silicon Dioxide (SiO2)
mineral
Biotite Granite
Phaneritic Felsic Igneous Rock
igneous
Native gold-bearing sulfide specimen
Native gold (Au), likely intergrown with pyrite (FeS₂) or chalcopyrite (CuFeS₂)
mineral
Epidote with quartz/feldspar
Epidote, Ca2(Al,Fe)3(SiO4)3(OH)
metamorphic
Bentonite Clay
Montmorillonite ((Na,Ca)0.33(Al,Mg)2Si4O10(OH)2·nH2O)
sedimentary
Hematite
Hematite (Fe2O3)
mineral
Dyed Blue Agate (Dragon Vein Agate)
Silicon Dioxide (SiO2) with artificial cobalt/organic dyes
mineral