Minerals

Pegmatitic gneiss with a quartz–feldspar vein

Quartz–feldspar-rich gneiss, locally cut by a granitic pegmatite vein

Granitic gneiss or weathered granite cobble

Quartz–feldspar–mica rock; likely gneiss (compositionally granite-derived)

Rose quartz-bearing rock

Quartz (SiO₂), likely massive rose quartz with iron-oxide staining

Lepidolite

K(Li,Al)3(Al,Si,3O8)2(F,OH)2

Pink feldspar pebble

Likely potassium feldspar (orthoclase or microcline; KAlSi₃O₈)

Fossil shell fragment

Indeterminate fossilized mollusk shell; species cannot be identified from the image

Blue kyanite in quartz-rich matrix

Kyanite, Al₂SiO₅, in a quartz- and mica-bearing metamorphic rock

Lepidolite

K(Li,Al)3(Si,Al)4O10(F,OH)2

Granite

Phaneritic felsic intrusive igneous rock

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Extrusive volcanic rock)

Mineral Sand (Heavy Mineral Sand Concentrate)

Placer deposit concentrate containing minerals such as ilmenite, rutile, zircon, and magnetite

Rhodonite

Inosilicate, (Mn,Fe,Mg,Ca)SiO3

Limonite / Ironstone Concretion

Hydrated Iron Oxide (FeO(OH)·nH2O)

Limonite

FeO(OH)·nH2O

Chrysocolla

Hydrated copper phyllosilicate, (Cu,Al)2H2Si2O5(OH)4·nH2O

Limonite

FeO(OH)·nH2O

Pyrite in Quartz

FeS2 (Iron Pyrite) with SiO2 (Quartz)

Fossilized Shark Tooth

Chondrichthyes tooth

Quartz

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite

Nephrite Jade

Nephrite

Rounded, mottled river pebble

Unidentified fine-grained rock; the image is insufficient for a reliable species-level identification

Kfeldspar with Quartz

Potassium Feldspar and Silicon Dioxide (KAlSi3O8 + SiO2)

Quartz Vein with Sulfides

Silicon Dioxide with Pyrite and Tourmaline (SiO2)

Limonite

FeO(OH)·nH2O

Granitic Gneiss

Gneiss (Complex silicate composition)

Limonite

FeO(OH)·nH2O

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Granite Gneiss

Gneiss (High-grade regional metamorphic rock)

Granite

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica or amphibole.

Tumbled milky quartz

Quartz, silicon dioxide (SiO₂)

Quartz Crystal Cluster on Matrix

Silicon Dioxide (SiO2)

Mixed Mineral and Crystal Assortment

Various silicate and oxide minerals

Serpentinite (likely)

Serpentinite; predominantly serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relic olivine/pyroxene

Pegmatite

Granitic pegmatite, chiefly quartz, feldspar, and mica

Quartz with Inclusions

Silicon Dioxide (SiO2)

Likely amphibolite

Amphibolite, composed mainly of hornblende (amphibole) and plagioclase feldspar

Milky quartz

Quartz (silicon dioxide, SiO₂)

Quartz Grain

Silicon Dioxide (SiO2)

Quartz

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz pebble

Silicon dioxide (SiO2)