Basalt with Iron Oxidation
Extrusive Mafic Igneous Rock (composed of Plagioclase and Pyroxene)
igneous
Category
Metamorphic Rock (Specifically A Rock Composed Of Minerals)
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Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
igneous
Sandstone
Sandstone (Quartz-rich sedimentary rock)
sedimentary
Granite (Pink/Potassium Feldspar Granite)
Felsic Plutonic Rock (Potassium Feldspar, Quartz, Mica, and Amphibole)
igneous
Granodiorite
Granodiorite (Quartz-Feldspar-Biotite Plutonic Rock)
igneous
Red Sandstone
Arenite (primarily composed of SiO2 with Fe2O3 cement)
sedimentary
Quartzite
Quartzite (composed primarily of Silicon Dioxide, SiO2)
metamorphic
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Biotite/Amphiboles)
metamorphic
Epidote
Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Rounded quartz-rich pebble
Quartzite (probable), composed predominantly of quartz (SiO₂)
metamorphic
Chalcedony / Quartz Nodule (Agate Pebble)
Silicon Dioxide (SiO2)
mineral
Sandstone
Arenite (Sedimentary rock)
sedimentary
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Weathered foliated metamorphic rock, likely schist or gneiss
Micaceous quartz–feldspar metamorphic rock; exact mineralogy requires testing
metamorphic
Black Slate
Slate (Metamorphic Rock)
metamorphic
Quartz (specifically Quartzite or Massive Quartz)
Silicon Dioxide (SiO2)
Mineral
Pegmatite (Granitic Pegmatite)
Pegmatite (Quartz + Potassium Feldspar + Mica)
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Red Sandstone
Sedimentary Clastic Rock (Quartz Arenite)
sedimentary
Quartz Crystal (specifically Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Chrome Diopside
Magnesium Calcium Silicate (MgCaSi2O6) containing Chromium impurities
mineral
Granitic Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Sandstone
Arenite
sedimentary
Sandstone
Sedimentary Rock (Quartz/Feldspar grains cemented together)
sedimentary
Sandstone (with secondary weathering/concretion)
Arenite (composed primarily of Quartz, SiO2)
sedimentary
Clear Quartz Crystal
Silicon Dioxide (SiO2)
mineral
Banded Gneiss
Gneiss (Metamorphic rock)
metamorphic
Sandstone
Arenite
sedimentary
Quartz in Matrix (Lepidolite or Quartzite)
Silicon Dioxide (SiO2) with host rock
mineral
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2 with various cementing agents)
sedimentary
Gneiss (likely)
Gneiss
Metamorphic
River Siltstone / Mudstone Pebble
Siltstone (composed of mixed silicate and carbonate minerals)
sedimentary
Gneiss
Gneissic Metamorphic Rock
metamorphic
Quartz Pebble (with Feldspar/Mica)
Granitic Quartz / SiO2 with KAlSi3O8
igneous
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains)
sedimentary
Quartzite River Rock
Quartzite (primarily SiO2)
metamorphic
Vesicular basalt
Basalt, a mafic volcanic rock composed mainly of plagioclase feldspar, pyroxene, and often olivine
igneous
Granite
Felsic intrusive igneous rock
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
mineral