Not A Rock Or Mineral (Anthropogenic Material)

Unknown small pale rock fragment

Unidentified light-colored granular mineral aggregate; likely quartz-rich material or limestone

Sandstone Pebble

Arenite (SiO2 complex)

Limonite (Iron Ore)

FeO(OH)·nH2O

Shark Tooth Fossil

Vertebrate fossilized tooth

Sandstone

Arenite (SiO2 based)

Schist

Schist (Metamorphic Rock)

Sandstone

Clastic sedimentary rock (Quartz arenite)

Mixed polished rock/mineral specimens

Indeterminate from image; likely quartz-bearing material with iron-oxide staining and possibly mica-rich schist

Sandstone

Sedimentary Rock (Quartz arenite or arkose)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 oxides)

Uncertain small stone; possibly weathered quartz-bearing rock

Indeterminate from image; candidate materials include quartz-rich pebble or altered silicate rock

Possible dark cobble or pebble

Unidentified rock; composition cannot be determined from the image

Sandstone

Arenite (SiO2 dominant)

Rough turquoise-bearing rock (probable turquoise matrix)

Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O, likely in a host-rock matrix

Fossil shell fragment in sedimentary rock

Indeterminate marine mollusk shell; likely a bivalve or gastropod fossil

Banded gneiss pebble

Gneiss, commonly quartz–feldspar–mica gneiss

Gneiss, likely migmatitic or granitic gneiss

Banded quartz–feldspar–mica gneiss; composition chiefly quartz, alkali/plagioclase feldspar, biotite and accessory minerals

Sandstone (likely Quartzose Sandstone)

Arenite (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Sandstone

Arenite

Weathered granite or granitic gneiss

Granite; predominantly quartz, feldspar, and mica (exact identification is uncertain from the image)

Sandstone

Arenite (SiO2 based)

Sandstone

Arenite (composed primarily of SiO2)

Raw Agate (Rough Lake Superior Agate or Jasper-Chalcedony Nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz-bearing rock, possibly pegmatite

Likely quartz and feldspar with dark mica or other accessory minerals; exact rock type is uncertain from the image

Cowrie shell

Marine gastropod shell; likely a cowrie (family Cypraeidae), species not identifiable from the image

Sandstone

Arenite

Sandstone

Arenite (SiO2 primarily)

Sandstone

Arenite (primarily SiO2)

Rhinestone

Artificial Glass/Crystal

Sandstone

Arenite (SiO2 based)

Granite (weathered, possibly porphyritic)

Granite; primarily quartz (SiO₂), feldspars, and mica/amphibole

Milky quartz

Quartz (silicon dioxide, SiO₂)

Quartz-rich chalcedony (likely silicified rock)

Microcrystalline quartz, SiO₂; possibly silicified limestone or jasper

Green glassy gemstone-like specimen

Likely synthetic glass or treated quartz; exact identification requires testing

Quartz

Silicon Dioxide (SiO2)

Honey calcite (likely rough cleavage fragment)

Calcite, calcium carbonate (CaCO₃)

Weathered quartz-bearing rock, possibly serpentine or altered ultramafic rock

Provisional identification: serpentinite or chlorite–quartz schist; exact composition requires testing

Granite

Intrusive Igneous Rock