Limonite (Yellow Ochre)
Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)
mineral
Category
Sedimentary (Secondary Classification: Cryptocrystalline Quartz)
Browse sedimentary (secondary classification: cryptocrystalline quartz) specimens identified by the Rock Identifier community.
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Sandstone with Liesegang Rings
Arenite with Iron Oxide Concretions
sedimentary
Tiger's Eye
Silicon dioxide (SiO2) with fibrous inclusions of crocidolite
Mineral
Limestone with Calcite
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Igneous
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Limonite (Iron Ore)
Limonite (Hydrous iron(III) oxide-hydroxide mixture, FeO(OH)·nH2O)
mineral
Native Copper
Native Copper (Cu)
mineral
Carnelian
SiO2 (Silicon Dioxide, variety of Chalcedony)
mineral
Basalt with Quartz Veins
Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)
igneous
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic volcanic rock)
igneous
Basalt with Amygdaloidal Inclusions
Aphanitic Mafic Volcanic Rock (Basalt)
igneous
Conglomerate with Quartz Inclusions
Conglomerate (clastic sedimentary rock) with internal Quartz (SiO2)
sedimentary
Quartzite and Jasper Pebbles
Quartzite (re-crystallized Quartz) and Cryptocrystalline Quartz (SiO2)
metamorphic
Quartz on Schist
Silicon Dioxide (SiO2) on Foliated Metamorphic Rock
metamorphic
Dragon Vein Agate (Dyed/Treated)
Agate (SiO2)
mineral
Dzi Bead (Agate)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
mineral
Blue Agate (Dyed)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
mineral
Limonite (Iron Ore)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Porphyritic Basalt (with Quartz or Calcite inclusion)
Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)
igneous
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Basalt with Quartz/Calcite matrix
Basalt (SiO2 with Ca/Mg/Fe silicates) on a Mineral Matrix
igneous
Amygdaloidal Basalt with Agate/Quartz Infill
Basalt with Secondary Silicate Mineralization (SiO2)
igneous
Limestone River Cobble
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Basalt with Quartz/Calcite Inclusions
Mafic Volcanic Rock (Fe-Mg silicate rich)
igneous
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Basalt with Quartz/Calcite Veining
Basalt (principally Plagioclase and Pyroxene)
igneous
Banded Agate (Polished Slice)
Chalcedony (SiO2) with Quartz
mineral
Banded Iron Formation
Banded Iron Formation (BIF)
Sedimentary Rock
Limestone (Ocherous)
Calcium Carbonate (CaCO3) with Iron Oxide (Limonite)
sedimentary
Limestone with Calcite Veins
Calcium Carbonate (CaCO3)
sedimentary
Basalt with Quartz Veins
Amygdaloidal Basalt (matrix) with Crystalline SiO2 (veins)
igneous
Pyrite
Iron Pyrite (FeS2)
mineral
Pink Stained Rock (Likely Quartzite or Sandstone with Iron Oxide Staining)
Quartzite (metamorphic) or Sandstone (sedimentary); coloration likely due to hematite or other iron oxides.
Metamorphic or Sedimentary (with staining)
Quartz Vein in Sedimentary Matrix
Silicon Dioxide (SiO2) with host rock
mineral
Psilomelane (Black Hematite/Manganese Ore)
Barium Manganese Oxide (Formula: BaMn9O18(OH)4)
mineral
Red Jasper (River Pebble)
Silicon Dioxide (SiO2) with hematite impurities
sedimentary (microcrystalline quartz)
Banded Agate Geode
Silicon Dioxide (SiO2)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated Iron Oxide)
mineral