Gneiss (specifically Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Category
Sedimentary Or Igneous (Secondary Formation)
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Quartz
Silicon Dioxide (SiO2)
mineral
Black Marble
Recrystallized Carbonate Rock (CaCO3)
metamorphic
Sandstone (Limonitic/Iron-stained)
Sandstone (containing Quartz, SiO2, and Limonite, FeO(OH)·nH2O)
sedimentary
Tumbled citrine quartz (probable)
Quartz, silicon dioxide (SiO₂), yellow variety commonly called citrine
mineral
Quartz (Tumbled)
Silicon Dioxide (SiO2)
mineral
Basalt-Amugydule (Amygdaloidal Basalt)
Aphanitic Mafic Igneous Rock with Vesicle Infillings
igneous
Pink Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
White Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Magnetite (Lodestone variant potential)
Magnetite (Fe3O4)
mineral
Hematite
Iron Oxide (Fe2O3)
mineral
Hematite
Iron Oxide (Fe2O3)
mineral
Hematite
Iron Oxide (Fe2O3)
mineral
White Quartz
Silicon Dioxide (SiO2)
mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Banded Agate (specifically Carnelian Agate slice)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
mineral
Magnetite / Iron Ore
Magnetite (Fe3O4)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Rounded gray pebble (likely fine-grained volcanic or sedimentary rock)
Undetermined from image; possibly andesite or a fine-grained sandstone
igneous
Pyrite-rich Volcanic Rock
Iron Disulfide (FeS2) in Volcanic Matrix
igneous
Quartz with Iron Oxide Stain
Silicon Dioxide (SiO2) with Hematite/Limonite coatings
mineral
Quartz Geode (Nodule)
Silicon Dioxide (SiO2)
sedimentary or igneous
Ferruginous Quartz
Iron-stained Quartz (Silicon Dioxide, SiO2 with Fe2O3 inclusions)
mineral
Turquoise color-bead and Hematite necklace
Turquoise (CuAl6(PO4)4(OH)8·4H2O) and Hematite (Fe2O3)
mineral
Green Quartz (including Prase or Aventurine variants)
Silicon Dioxide (SiO2) with inclusions (likely Actinolite or Chlorite)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Turquoise
Turquoise (Hydrated copper aluminum phosphate, CuAl6(PO4)4(OH)8·4H2O)
Mineral
Bloodstone / Heliotrope
Silicon dioxide (SiO2) with inclusions
Mineral (variety of Chalcedony)
Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)
metamorphic
Pyrite Cube in Matrix
Iron Sulfide (FeS2)
mineral
Banded Chalcedony (Agate)
Chalcedony (SiO2) - Cryptocrystalline Quartz
mineral
Carnelian
Carnelian (a variety of Chalcedony, SiO ₂)
Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Blue-dyed Quartz Druzy
Silicon Dioxide (SiO2) with artificial pigment
mineral
Iron-rich weathered rock (likely limonite/goethite concretion)
Limonite–goethite mixture; chiefly FeO(OH)·nH₂O
mineral
Agate
Silicon Dioxide (SiO2)
mineral
Polished blue copper mineral, likely chrysocolla or dyed howlite
Chrysocolla: hydrated copper phyllosilicate, approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O; visual identification is uncertain from the image
mineral
Quartz (Variety: Agate / Chalcedony)
Silicon Dioxide (SiO2)
sedimentary
Amygdaloidal Basalt with Quartz
Basalt with Secondary Mineral Infilling
igneous
Vesicular Basalt
Basalt with secondary mineral infills
igneous