Gossan
Iron-rich regolith (mainly Limonite and Goethite, FeO(OH)·nH2O)
sedimentary
Category
Minerals
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Bumblebee Jasper (technically Bumblebee Stone)
Calcite, Aragonite, and Realgar/Orpiment mixture (SiO2 + CaCO3 + As2S3/As2S2)
sedimentary (volcanic)
Milky quartz
Quartz (silicon dioxide, SiO₂)
mineral
Gneiss
Gneiss (Metamorphic high-grade)
metamorphic
Kyanite
Al2SiO5
mineral
Limonite
FeO(OH)•nH2O
mineral
Limonite
FeO(OH)•nH2O
mineral
Quartz Vein Rock
Silicon dioxide (SiO2) within a host rock matrix
mineral
Mixed Mineral Collection
Multiple Mineral Species (Silicates and Oxides)
mineral
Basalt with Quartz/Zeolite Inclusions
Porphyritic Basalt (SiO2 with Aluminosilicates)
igneous
Chatoyant Quartz (Cat's Eye Quartz)
Silicon Dioxide (SiO2) with fibrous inclusions of Amphibole or Rutile
mineral
Weathered sandstone or siltstone
Likely iron-oxide-stained siliciclastic sedimentary rock; exact composition cannot be confirmed from the photo
sedimentary
Rounded fine-grained dark pebble
Likely basalt or basaltic volcanic rock; exact identification requires testing
igneous
Clear quartz crystal (probable)
Quartz, silicon dioxide (SiO₂)
mineral
Rounded quartz-rich pebble, likely milky quartz with iron-oxide inclusions
Quartz (SiO₂), possibly with minor chlorite or iron/manganese oxides
mineral
Serpentine-rich metamorphic rock
Serpentinite; chiefly antigorite/lizardite/chrysotile, commonly with magnetite and carbonate
metamorphic
Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
mineral
Eclogite
Eclogite (Omphacite-Garnet rock)
metamorphic
Quartz Pebble (with Dark Volcanic/Sedimentary Inclusion)
Silicon Dioxide (SiO2)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Mahogany Obsidian
Volcanic glass containing Magnetite/Hematite
igneous
Quartz with Chlorite or Hornblende inclusions
Silicon dioxide (SiO2) with phyllosilicate or amphibole inclusions
metamorphic
Gabbro or Diorite with Quartz/Epidote Vein
Intrusive Igneous Rock (Plutonic)
igneous
Granite (granitoid pebble)
Felsic intrusive igneous rock, chiefly quartz and feldspar with dark biotite or amphibole
igneous
Iron-rich banded quartzite / jaspilite
Banded iron formation (BIF), chiefly quartz (SiO₂) and iron oxides (hematite, Fe₂O₃; magnetite, Fe₃O₄)
metamorphic
Small green-gray pebble (likely serpentinite)
Serpentinite, composed mainly of serpentine-group minerals
metamorphic
Gneiss
Gneiss
metamorphic
K-Feldspar
Potassium Feldspar (KAlSi3O8)
mineral
Galena
Lead(II) sulfide (PbS)
mineral
Banded gneiss pebble
Gneiss, composed chiefly of quartz, feldspar, and mica/amphibole
metamorphic
Greenstone / altered basalt (probable)
Chlorite–epidote–actinolite aggregate; commonly metabasalt (greenstone)
metamorphic
Amphibolite (likely)
Amphibolite, chiefly hornblende and plagioclase feldspar
metamorphic
Pegmatite fragment
Granitic pegmatite, composed mainly of quartz, feldspar, and mica
igneous
Lepidolite
K(Li,Al)3(Al,Si,V)4O10(F,OH)2
mineral
Granitic Gneiss
Gneiss (high-grade metamorphic rock)
metamorphic
Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Metamorphic Rock
Weathered porphyritic volcanic rock (likely basalt/andesite)
Fine-grained mafic to intermediate volcanic rock; probably porphyritic basalt or andesite, composed mainly of plagioclase with pyroxene and iron oxides
igneous
Weathered serpentine or serpentinite
Serpentine-group minerals, chiefly antigorite, lizardite, and chrysotile; commonly Mg₃Si₂O₅(OH)₄
metamorphic
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral