Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Category
Browse mineral like byproduct (technogenic) specimens identified by the Rock Identifier community.
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Turquoise and Hematite
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)
Jasper (Iron-rich)
Silicon Dioxide (SiO2) with Fe2O3 (Hematite) impurities
Turquoise
Turquoise (CuAl6(PO4)4(OH)8·4H2O)
Quartz with Inclusions
Silicon Dioxide (SiO2) with various mineral inclusions
Amygdaloidal Basalt
Vesicular Basalt with secondary mineral infilling (commonly Zeolite, Calcite, or Quartz)
Riverstone Jasper (Chert variant)
Silicon Dioxide (SiO2)
Prehnite
Calcium aluminum silicate hydroxide - Ca2Al(AlSi3O10)(OH)2
Epidote
Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)
Banded Gneiss
Gneiss (High-grade metamorphic rock)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides
Blue Sapphire
Corundum (Al2O3 with trace Titanium and Iron)
Chalcanthite (Likely Synthetic/Lab-Grown)
Hydrated copper(II) sulfate (CuSO4·5H2O)
Blue Apatite
Chlorapatite / Fluorapatite (Ca5(PO4)3(F,Cl,OH))
Yellow Aventurine
Quartzite with inclusions (SiO2)
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS) with Quartz (SiO2)
Emerald / Green Beryl
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
Psilomelane (Black Hematite/Manganese Ore)
Barium Manganese Oxide (Formula: BaMn9O18(OH)4)
Sandstone
Arenite (primarily SiO2)
Chrysocolla
Chrysocolla - (Cu,Al)2H2Si2O5(OH)4·nH2O
Basalt
Mafic Igneous Rock
Clear Quartz (Tumbled)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Dendritic Opal (Merlinite)
Hydrated Silica with Manganese/Iron oxide inclusions (SiO2·nH2O)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Limonite (Pseudomorph after Pyrite/Marcasite)
Hydrated Iron Oxide (FeO(OH)·nH2O)
Silicon Carbide (Carborundum)
Moissanite (SiC), though mostly synthetic
Septarian Nodule (Septarian Dragon Stone)
Septarian concretion (composition: Calcite CaCO3, Aragonite CaCO3, and Limestone/Clay)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Bauxite
Bauxite (mixture of Gibbiste Al(OH)3, Boehmite ̳-AlO(OH), and Diaspore ́-AlO(OH))
Diorite
Diorite (intermediate intrusive igneous rock)
Limonite (Ironstone)
Limonite (FeO(OH)·nH2O)
Conglomerate
Clastic sedimentary rock (Puddingstone)
Conglomerate
Conglomerate (a clastic sedimentary rock)
Geode (Unopened)
Silica-lined Vug (primarily SiO2)
N/A (Non-Geological Specimen)
Yellow Ocher (Limonite)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
Sandstone
Arenite (SiO2 based)
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)
Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)