Chalcedony (Desert Rose or Botryoidal Chalcedony)
Silicon Dioxide (SiO2)
mineral
Category
Sedimentary (Secondary Mineral Formation)
Browse sedimentary (secondary mineral formation) specimens identified by the Rock Identifier community.
Hematite
Iron(III) oxide (Fe2O3)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Hematite
Iron(III) oxide (Fe2O3)
Mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
metamorphic
Chrysocolla in Matrix
Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Crystal Quartz Beads (likely Clear Quartz)
Quartz (SiO₂)
Mineral
Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Granite
Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)
Igneous
Agate
Silicon dioxide (SiO2) - variety Chalcedony
mineral
Banded Agate
Silicon Dioxide (SiO2)
mineral
Fluorite (likely)
Calcium Fluoride (CaF2)
Mineral
Pietersite
Brecciated Crocidolite in Quartz (Chalcedony)
metamorphic
Carnelian
Carnelian (Silicon Dioxide, SiO2)
mineral
Red Jasper
Silicon dioxide (SiO2) with Iron inclusions
sedimentary
Silver (Native Silver)
Native Silver (Ag)
mineral
Yellow Aventurine
Quartz (Silicon Dioxide - SiO2) with inclusions of Mica
Mineral
Chert (Flint variety)
Chert (SiO2)
sedimentary
Red Garnet
Garnet Group (e.g., Pyrope, Almandine, Spessartine, Grossular, Andradite, Uvarovite)
Mineral
Magnetite
Magnetite (Iron(II,III) oxide, Fe3O4)
mineral
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3)
sedimentary
Sandstone (with Iron Staining)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
sedimentary
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Sandstone-based Concrete Fragment
Cementitious Composite with Sedimentary Aggregate
sedimentary (man-made/anthropogenic)
Microcrystalline Limestone Pebble
Carbonate sedimentary rock (Calcium Carbonate, CaCO3)
sedimentary
Petoskey Stone
Hexagonaria percarinata
sedimentary
Banded Chert with Quartz Veining
Microcrystalline Quartz (SiO2)
sedimentary
Magnetite
Magnetite (Fe3O4)
Mineral
Basalt with vesicles (Amygdaloidal Basalt)
Amygdaloidal Basalt (predominantly Plagioclase and Pyroxene)
igneous
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Quartz Vein in Host Rock (Likely Slate or Shale)
Hydrothermal Quartz (SiO2) in Pelitic host rock
metamorphic
Yellow Ochre / Limonite
Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)
mineral
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
mineral
Turquoise
Turquoise (CuAl6(PO4)4(OH)8·4H2O)
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Chrysocolla and Azurite in Matrix
Hydrated copper phyllosilicate (Chrysocolla - Cu2H2Si2O5(OH)4) and Copper carbonate (Azurite - Cu3(CO3)2(OH)2)
mineral
Azurite Malachite (Mixed)
Azurite-Malachite; Azurite: Cu3(CO3)2(OH)2 / Malachite: Cu2CO3(OH)2
mineral