Igneous And Metamorphic Derivative (Weathered)

Reddish-brown crystalline rock, possibly weathered granite or garnet-bearing schist

Indeterminate; likely quartz–feldspar–mica rock with iron oxides, potentially garnet-bearing

Quartz fragment (Pebble)

Silicon Dioxide (SiO2)

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Weathered, rounded polymictic pebble (likely volcanic or metamorphic rock)

Indeterminate; possibly altered basalt, greenstone, or epidote-bearing metamorphic rock

Quartz Pebble

Silicon Dioxide (SiO2)

Pyrite in Matrix (likely Quartz or Schist matrix)

Iron Sulfide (FeS2)

Granite / Gneiss (Felsic Metamorphic or Igneous Rock)

Gneiss (or weathered Granite)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Weathered granitic gneiss or granite cobble

Granite–gneiss, chiefly quartz, feldspar, and dark mica/amphibole

Quartz-rich pebble (likely milky quartz)

Quartz, SiO₂

Quartz pebble

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Iron-stained Quartz

Silicon Dioxide with Iron Oxide (SiO2 with Fe2O3)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Small dark mineral or rock fragment

Undetermined; possibly a dark mafic mineral such as biotite or magnetite

Weathered quartz-rich mineral nodule

Likely quartz (SiO₂) with iron-oxide staining and possibly feldspar/mica; exact identification requires testing

Biotite Mica Schist

Metamorphic Rock containing Biotite K(Mg,Fe)3AlSi3O10(OH)2

Weathered quartz-rich pebble, possibly granite or granodiorite

Felsic intrusive rock; chiefly quartz, feldspar, and minor mica/amphibole

Quartz (Quartzite / Iron-stained Quartz)

Silicon Dioxide (SiO2)

Quartz (Smoky/Milky)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Likely weathered quartz-bearing rock fragment

Indeterminate; appears to contain quartz (SiO₂) with iron-oxide staining, possibly from quartzite, granite, or pegmatite

Quartz (Small Pebble)

Silicon Dioxide (SiO2)

Likely clear quartz pebble or glassy quartz fragment

Quartz (silicon dioxide, SiO₂)

Pyrite

Iron Sulfide (FeS2)

Garnet (Almandine/Pyrope series)

Garnet Group - X3Y2(SiO4)3

Small rounded pebble, likely quartz-rich stone

Indeterminate; possibly quartzite or light-colored granitoid, composed mainly of quartz and feldspar

Small tumbled brown mineral specimen

Likely quartz variety or iron-stained feldspar; exact identification is uncertain from the image

Small weathered mineral/rock fragment

Unidentified; likely quartz-rich material, possibly quartzite or feldspar-bearing rock

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (Milky or Yellow/Citrine Quartz)

Silicon Dioxide (SiO2)

Agate

Silicon Dioxide (Chalcedony), SiO2

Feldspar (Orthoclase)

Potassium Feldspar (KAlSi3O8)

Small quartz-rich pebble, possibly milky quartz

Quartz (silicon dioxide, SiO₂)

Corundum (Sapphire/Ruby in Matrix)

Aluminium oxide (Al2O3)

Milky Quartz Pebble

Silicon Dioxide (SiO2)