Basalt (River Rock/Cobble)
Basalt (no specific mineral formula as it's a rock)
Igneous
Category
Mineral_rock
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Note regarding baguette production (not a rock)
Digital text image - Somali language
not a rock
Greenstone / Greenschist
Greenschist facies metamorphic rock
metamorphic
Greenish rock with white veins, possibly epidote or chlorite bearing rock with quartz/calcite veins
Altered mafic rock or Epidosite
metamorphic or igneous alteration
Granite
Granite (Felsic intrusive igneous rock)
igneous
River Cobble (likely Siltstone or Sandstone)
Clastic Sedimentary Rock
sedimentary
Quartz with Tourmaline or Amphibole
Silicon Dioxide with silicate inclusions (SiO2)
mineral
Gossan (Iron Cap)
Limonitic Gossan (FeO(OH)·nH2O)
sedimentary
Microcline Feldspar
KAlSi3O8
mineral
Epidote
Epidote (Ca2(Al, Fe)3(SiO4)3(OH))
mineral
Landscape Boulder / River Rock
Granitic or Quartzite Rock
igneous
Granite / Diorite Xenolith or Contact
Felsic-Mafic Intrusive Igneous Rock
igneous
Limonite (Yellow Ochre)
FeO(OH)·nH2O (Hydrous iron(III) oxide-hydroxide mixture)
Mineral (Iron Ore)
Quartz (specifically Quartzite or Massive Quartz)
Silicon Dioxide (SiO2)
Mineral
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Granodiorite
Granodiorite
Igneous
Quartz
Silicon Dioxide (SiO2)
mineral
Fossilized Shark Tooth (Megalodon or Carcharocles fragment)
Elasmobranchii (Fossilized tooth root / crown section)
fossil
Quartz Vein in Host Rock (Gossanous Matrtix)
Silicon Dioxide (SiO2) with iron oxides (Limonite/Hematite)
mineral
Banded Sandstone
Clastic Sedimentary Rock (Quartz Arenite)
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz Druzy on Matrix
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
fossil
Quartz crystal cluster
Quartz (silicon dioxide, SiO₂)
mineral
Milky Quartz Pebble with Matrix
Quartz (Silicon Dioxide, SiO2)
mineral
Bivalve Seashell Fossil
Class Bivalvia
fossil
Red Sandstone
Arenite (with Iron Oxide)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Banded Sedimentary Rock
Sedimentary rock with Liesegang banding
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Quartz (Milky/Crystalline fragment)
Silicon Dioxide (SiO2)
mineral
Biotite (Mica)
Biotite group (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Polished Black Obsidian
Volcanic Glass (70-75% SiO2)
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Goethite (Iron Ore)
Goethite (FeO(OH))
mineral
Sandstone (specifically Lithic or Quartz Arenite)
Arenite (composed primarily of SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Red Sandstone Pebble
Arenite (primarily Quartz SiO2 with Hematite Fe2O3 staining)
sedimentary
Basalt with Secondary Mineralization (Likely Zeolites or Calcite)
Aphanitic mafic volcanic rock with secondary mineral inclusions (e.g., CaAl2Si3O10·3H2O for Scolecite)
igneous
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Calcite
Calcium Carbonate (CaCO3)
mineral
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
sedimentary