Likely limonite/goethite-rich ironstone
Limonite (amorphous hydrated iron oxides), commonly mixed with goethite, hematite, and host rock
mineral
Category
Mixed: Igneous And Sedimentary
Browse mixed: igneous and sedimentary specimens identified by the Rock Identifier community.
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Polished magnetite-rich ironstone (possible magnetite pebble)
Magnetite, Fe₃O₄; possibly magnetite-bearing basalt or ironstone
mineral
Polished red jasper
Jasper, microcrystalline quartz (SiO₂), colored by iron oxides and commonly mixed with chalcedony or other minerals
mineral
Chalcedony (Agate/Carnelian precursor)
Chalcedony (Silicon Dioxide, SiO2)
mineral
Pyrite in Quartz Matrix
Iron Disulfide (FeS2) in Silicon Dioxide (SiO2)
mineral
Amethyst
Amethyst (Silicon Dioxide - SiO2 with iron impurities)
mineral
Rhodonite
Rhodonite, manganese inosilicate — MnSiO₃; the specimen may include quartz, feldspar, and black manganese-oxide minerals in the matrix
mineral
Carnelian (Tumbled)
Carnelian (Chalcedony / Silicon Dioxide, SiO2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Black Tourmaline (Schorl)
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
mineral
Fine-grained brown sand or weathered soil
Unconsolidated siliciclastic sediment, likely quartz-rich sand (SiO₂) mixed with iron-oxide-coated grains
sedimentary
Dearest Ring (Gemstones)
Mixed Gemstones: Diamond (C), Emerald (Be3Al2Si6O18), Amethyst (SiO2), Ruby (Al2O3), Sapphire (Al2O3), Topaz (Al2SiO4(F,OH)2)
mineral
Quartz (Milky/Smoky variety on matrix)
Silicon Dioxide (SiO2)
mineral
Ironstone / limonite-rich rock
Limonite, chiefly hydrated iron oxides (FeO(OH)·nH₂O), commonly mixed with goethite and hematite
mineral
Tumbled milky quartz
Quartz (silicon dioxide, SiO₂)
mineral
Milky quartz crystal cluster
Quartz (silicon dioxide, SiO₂)
mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Likely milky quartz
Quartz (silicon dioxide, SiO₂)
mineral
Magnetite / Ironstone
Magnetite (Fe3O4)
mineral
Mookaite Jasper
Siliceous sedimentary rock (variety of Jasper/Chert)
Sedimentary Rock
Milky quartz
Quartz (silicon dioxide, SiO₂)
mineral
Black Tourmaline (Schorl)
Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3)(OH)3(OH))
mineral
Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Small quartz-rich mineral fragment
Quartz (SiO₂), possibly milky or chalcedonic quartz
mineral
Quartz
Silicon dioxide (SiO2)
mineral
Dalmatian Jasper
Aplite with Arfvedsonite inclusions
igneous
Magnetite (Lodestone variety)
Magnetite (Fe3O4)
mineral
Magnetite
Iron(II,III) oxide (Fe3O4)
mineral
Quartz pebble
Silicon dioxide (SiO2)
mineral
Clear Quartz
SiO2 (Silicon Dioxide)
gemstone
Mica
Mica group (often Muscovite or Biotite)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Milky quartz
Quartz, silicon dioxide (SiO₂)
mineral
Shale
Shale
sedimentary
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
mineral
Quartz Heart or Arrowhead Shape
Silicon Dioxide (SiO2)
mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Quartz (Rose Quartz or Jasper variety)
Silicon Dioxide (SiO2)
mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Apatite
Calcium phosphate fluoride/chloride, Ca5(PO4)3(F,Cl,OH)
mineral