Rhodochrosite
Manganese carbonate (MnCO3)
Category
Browse mixed: igneous and sedimentary specimens identified by the Rock Identifier community.
Rhodochrosite
Manganese carbonate (MnCO3)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Quartz (likely milky/gray variety)
Quartz (SiO₂)
Chalcedony (Banded/Mottled Variety)
Chalcedony (a cryptocrystalline variety of Quartz, SiO2)
Muscovite Mica
Muscovite (KAl₂(AlSi₃O₁₀)(F,OH)₂))
Amethyst
Amethyst (Silicon Dioxide with iron impurities, SiO2)
Hypersthene
(Mg,Fe)SiO3 - Enstatite-Ferrosilite series
Smoky Quartz
Smoky Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Quartz (SiO₂)
Quartz
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide (Fe2O3) inclusions
Galena
Lead(II) sulfide (PbS)
Dyed Chalcedony (Agate)
Silicon Dioxide (SiO2) with artificial pigment
Jasper (specifically Red or Brecciated Jasper variant)
Jasper (Microcrystalline Quartz - SiO2)
Quartz (River Pebble)
Quartz (Silicon Dioxide, SiO2)
Peach Moonstone
Orthoclase Feldspar (KAlSi3O8)
Carnelian (a variety of Chalcedony)
Silicon Dioxide (SiO₂)
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
Blue Chalcedony
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO₂)
Milky Quartz with Iron Oxide Staining
Quartz (Silicon Dioxide, SiO2)
Citrine (likely Heat-Treated Amethyst)
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2) with iron oxide inclusions
Gneiss (Metamorphic Rock)
Gneiss
Banded Rock (likely Quartz-rich)
Uncertain, likely a Metamorphic Rock (e.g., Gneiss or Schist) with prominent Quartz and other minerals
Mica (likely Muscovite)
Muscovite / KAl2(AlSi3O10)(OH)2
Magnetite
Magnetite (Fe3O4)
Pyrite
Pyrite (FeS2)
Pyrite (or Fool's Gold)
Pyrite (FeS₂)
Tumbled Moonstone and Amazonite Chips
Orthoclase (KAlSi3O8) and Microcline (KAlSi3O8) of the Feldspar Group
Citrine
Citrine (Silicon Dioxide - SiO2)
Orbicular Jasper (Ocean Jasper tendency)
Silicon Dioxide (SiO2) with impurities
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Yellow Quartz (Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
Rutilated Quartz
Quartz (SiO2) with Rutile (TiO2) inclusions
Calcite
Calcite (CaCO₃)
Hematite (beads)
Hematite (Fe₂O₃)
Marble
Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.
Petrified Wood
Silicified Wood (SiO2)
Botryoidal Goethite on Quartz
Goethite (α-Fe3+O(OH)) on Quartz (SiO2)
Psilomelane (Black Hematite/Manganese Ore)
Barium Manganese Oxide (Formula: BaMn9O18(OH)4)