Mineral, Part Of A Rock

Iron-stained quartzite pebble

Quartzite, composed predominantly of SiO₂ (quartz), with iron-oxide staining

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily SiO2)

Rounded granite pebble

Granite, a quartz–feldspar–mica plutonic rock

Granite

Intrusive Igneous Rock

Sandstone (Quartzose Sandstone Pebble)

Arenite (primarily SiO2)

Pink Granite

Phaneritic intrusive igneous rock (Felsic)

Granite

Granite (Felsic Plutonic Rock)

Quartzite River Rock

Quartzite (SiO2)

Granite

Granite (Felsic Plutonic Rock)

Granite

Phaneritic Plutonic Felsic Rock

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Granite

Phaneritic plutonic rock (Quartz, Feldspar, Mica)

Granite

Granite (Felsic Plutonic Rock)

Granite

Granite (Felsic Plutonic Rock)

Bivalve Fossil (Clam)

Class Bivalvia, likely Mercenaria or similar genus

Note: Item is not a geological specimen

n/a

Sandstone Pebble

Arenite (primarily SiO2)

Carnelian

Carnelian (Cryptocrystalline Quartz, SiO2)

Granite

Phaneritic Felsic Igneous Rock

Likely shale or mudstone fragment

Fine-grained clastic sedimentary rock, composed mainly of clay minerals and silt-sized quartz; the image is insufficient to distinguish shale from mudstone confidently.

Weathered granite-like rock

Granite, likely biotite-bearing; exact identification is uncertain from the image

Weathered wood-like rock surface, likely slate or schist

Probable graphitic schist or slate; exact identification is uncertain from the image

Ferruginous Sandstone Pebble

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH) staining)

Painted River Rock (likely Quartzite or Granite)

Quartzite or Granitic Gneiss (painted)

Quartz Geode fragment

Crystalline Silicon Dioxide (SiO2)

Greenstone / Quartzite Pebble

Metamorphosed Quartz-rich Rock

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Likely dark rounded stone or mineral fragment

Indeterminate; possibly a water-worn mafic rock such as basalt

White quartz pebble (possibly milky quartz)

Quartz, SiO₂

Weathered granite or granitic gneiss pebble

Granite, primarily quartz, feldspar, and mica; exact identification is uncertain from the image

Quartz geode or druzy quartz nodule

Quartz, silicon dioxide (SiO₂), likely iron-oxide-stained chalcedony/quartz

Siltstone with Quartz Vein

Siltstone (primarily SiO2, Al2O3, Fe2O3)

Granite (Specimen: Logan Rock)

Phaneritic plutonic igneous rock (mainly Quartz, Feldspar, and Mica)

Pink Granite

Granite (Phaneritic igneous rock rich in Alkali Feldspar)

Granite

Granite (Phaneritic Quartz-Feldspar Rock)

Epidote

Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Quartzite

Quartzite (Primary mineral: SiO2)

Basalt (Volcanic Peak)

Extrusive Mafic Igneous Rock

Granite

Intrusive Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Granite

Granite