Moonstone
Orthoclase (KAlSi3O8) or Oligoclase with adularescence
gemstone
Category
Sedimentary Or Metamorphic (Low Grade)
Browse sedimentary or metamorphic (low grade) specimens identified by the Rock Identifier community.
Learn about Sedimentary Or Metamorphic (Low Grade) in the encyclopedia
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Weathered iron-stained quartzite or sandstone cobble
Quartzite (quartz-rich rock), possibly ferruginous sandstone
metamorphic
Yellow Quartzite (Iron-Stained Quartz)
Quartzite (SiO2 with Fe-oxide impurities)
metamorphic
Yellow Quartzite Pebble
Metamorphic rock predominantly composed of Quartz (SiO2)
metamorphic
Chalcedony on Matrix
Silicon Dioxide (SiO2)
mineral
Siltstone or Mudstone
Siltstone (composed primarily of silt-sized particles)
sedimentary
Gravel and Pebbles
Unconsolidated rock fragments / detrital sediment
sedimentary
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Rose Quartz
Silicon Dioxide (SiO2)
mineral
Likely weathered quartz-rich rock fragment
Uncertain; possibly granitic pegmatite or quartz-bearing metamorphic rock
igneous
Aquamarine
Beryllium aluminum silicate (Be3Al2Si6O18)
mineral
Tufa Rock and Tumbled Gemstones
Calcareous Tufa (Calcium Carbonate, CaCO3)
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Shale or Mudstone River Pebble
Argillaceous sedimentary rock
sedimentary
Yellow Quartz
Silicon Dioxide (SiO2)
mineral
Greenstone with Quartz Veining
Epidiorite or Metabasalt with SiO2 (Quartz) veins
metamorphic
Soapstone (Talc Schist)
Steatite
metamorphic
Bloodstone
Chalcedony (Variety: Bloodstone / Heliotrope), SiO2
mineral
Orange Carnelian / Chalcedony Pebble
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Green Jasper / Bloodstone
SiO2 (Microcrystalline Quartz)
mineral
Quartz (Chalcedony/Agate nodule)
Silicon dioxide (SiO2)
mineral
Carnelian Agate
Silicon Dioxide (SiO2) - Chalcedony with Iron Oxide impurities
mineral
Pyrite
Iron Pyrite (FeS2)
mineral
Carnelian
Carnelian (Chalcedony / Quartz variety, SiO2)
mineral
Blue Chalcedony
Silicon Dioxide (SiO2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Chalcedony (Milky Agate/Quartz)
Silicon Dioxide (SiO2)
mineral
Carnelian
Chalcedony (SiO2) with Iron Oxide inclusions
mineral
Pyrite in Matrix
Iron Sulfide (FeS2)
mineral
Serpentine (likely serpentinized ultramafic rock)
Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; commonly derived from peridotite
metamorphic
Eclogite
Eclogite (comprising Omphacite and Garnet)
metamorphic
Mica Schist
Medium-grade regional metamorphic rock (composition varies)
metamorphic
Schist
Mica Schist (Group of medium-grade metamorphic rocks)
metamorphic
Lapis Lazuli
(Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2 (Complex silicate rock)
metamorphic
Serpentinite
Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)
metamorphic
Stichtite in Serpentine (Atlantasite)
Mg6Cr2CO3(OH)16·4H2O in Mg3Si2O5(OH)4
metamorphic
Aragonite
Aragonite (CaCO3)
mineral
Serpentinite
Serpentinite (composed primarily of serpentine group minerals like lizardite, antigorite, and chrysotile)
metamorphic
Green aventurine (likely)
Quartz variety; silicon dioxide (SiO₂) with green fuchsite mica inclusions
mineral
Ferruginous Quartz
Iron-stained Quartz (SiO2 with Fe2O3 impurities)
mineral
Banded Gneiss
Gneiss (pronounced "nice")
metamorphic
Apatite
Apatite group mineral (e.g., Fluorapatite - Ca5(PO4)3F, Chlorapatite - Ca5(PO4)3Cl, Hydroxylapatite - Ca5(PO4)3(OH))
mineral