Black Tourmaline (Schorl)
Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3)(OH)3(OH))
mineral
Category
Metamorphic Or Igneous Alteration
Browse metamorphic or igneous alteration specimens identified by the Rock Identifier community.
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Quartz (likely Milky Quartz or Chalcedony)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Quartz
Quartz (SiO₂)
mineral
Bi-Color Tourmaline (or Watermelon Tourmaline)
Tourmaline (complex borosilicate mineral group with general formula AD3G6(BO3)3T6O18(OH,O)4)
Mineral
Quartz (likely a clear or rock crystal variety)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Milky Quartz
Quartz (SiO2)
Mineral
Quartz with Mica Schist (Pegmatite Specimen)
SiO2 (Silicon Dioxide) and Phyllosilicates (Biotite/Muscovite)
Igneous/Metamorphic Hybrid
Quartz
Silicon Dioxide (SiO₂)
Mineral
Greenstone (Greywacke or Nephrite Jade variant)
Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)
metamorphic
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Pyrite
Pyrite (Iron sulfide, FeS₂)
mineral
Calcite
Calcite (CaCO3)
mineral
Beryl (Variety Mix)
Be3Al2(Si6O18)
Mineral
Pegmatite (likely Granitic Pegmatite)
Pegmatite (a coarse-grained igneous rock, often with granitic composition)
igneous
Smoky Quartz
Smoky Quartz (SiO2)
Mineral
Zircon
Zircon (ZrSiO4)
Mineral
Rose Quartz
Rose Quartz (SiO2)
mineral
Banded Gneiss
Gneiss (pronounced 'nice')
metamorphic
Marble
Marble (primarily Calcite, CaCO3 or Dolomite, CaMg(CO3)2)
Metamorphic Rock
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Mineral
Mixed Quartz and River Pebbles (Stone Collection)
Mixed assortment containing mainly Silicon Dioxide (SiO2)
igneous, sedimentary, metamorphic, and mineral
Jasper
Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)
sedimentary
Crystal Quartz Beads (likely Clear Quartz)
Quartz (SiO₂)
Mineral
Rutilated Quartz
Quartz (SiO2) with Rutile (TiO2) inclusions
Mineral
Aventurine
Aventurine Quartz (SiO2 with inclusions)
Mineral
Labradorite
Labradorite (a variety of Plagioclase Feldspar), Na(AlSi3O8) to Ca(Al2Si2O8)
Mineral
Apatite
Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))
mineral
Rock Crystal Quartz
Quartz (SiO₂)
Mineral
Citrine
Quartz (SiO2) - specifically, a variety of macrocrystalline quartz
mineral
Banded River Cobble with Mafic Dike
Hydrothermally altered Graywacke or Sandstone with Mafic Intrusion
igneous and sedimentary
Pyrite
Pyrite (FeS2)
Mineral
Mica (likely Muscovite)
Muscovite / KAl2(AlSi3O10)(OH)2
mineral
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2) with various iron-oxide inclusions
mineral
River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
mixed
Muscovite Mica
Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2
Mineral
Gold Ore in Quartz/Schist
Auriferous Quartz and Sulfide-bearing Schist
Metamorphic/Igneous (Hydrothermal)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Metasedimentary or Igneous matrix
mineral
Quartz
Silicon Dioxide (SiO2)
Mineral
Quartz (River Pebble)
Quartz (SiO₂ - Silicon Dioxide)
Mineral