Mineral, Part Of A Rock

Likely polished tiger’s-eye with dark matrix

Quartz (SiO₂) with fibrous crocidolite-derived inclusions; possibly an iron-rich jasper or other dark host rock

Weathered basalt pebble

Basalt, a fine-grained mafic volcanic rock; chiefly plagioclase, pyroxene, and commonly olivine

Granite

Granite (Felsic Plutonic Rock)

Likely slate fragment

Slate; fine-grained foliated metamorphic rock composed mainly of clay minerals, quartz, and mica

Granite

Granite (Phaneritic Quartz-Feldspar Plutonic Rock)

Granite

Phaneritic plutonic rock (Quartz, Feldspar, Mica)

Dark vesicular volcanic rock, likely basaltic scoria

Scoria (vesicular basalt; composition commonly plagioclase, pyroxene, and iron-rich glass)

Garnet (Almandine)

Almandine (Fe3Al2(SiO4)3)

Weathered granite or granitic gneiss

Granite; mainly quartz (SiO₂), feldspar, and mica; possible weak gneissic texture

Small granitic rock fragment

Granite or granodiorite; chiefly quartz, feldspar, and minor mica/amphibole

Gabbro

Plutonic mafic rock

Rounded black-and-cream granite pebble

Granite, composed chiefly of quartz, feldspar, and dark mica or amphibole

Quartz-rich rock fragment

Likely quartz vein material, predominantly quartz (SiO₂); identification is tentative from the image

Chert with Calcite Veining

Microcrystalline Quartz (SiO2) with Calcium Carbonate (CaCO3) veins

Rounded quartz-rich pebble

Likely granitoid-derived quartz–feldspar cobble; exact identification requires testing

Granite Pebble

Granite (Felsic Intrusive Igneous Rock)

Granite

Intrusive Felsic Igneous Rock

Quartzite

Quartzite (SiO2)

Granite

Granite

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Weathered pink granite

Granite, chiefly quartz, potassium feldspar, plagioclase, and biotite

Granite

Granite (Phaneritic igneous rock)

Rounded sandstone pebble

Quartz-rich sandstone (likely arkosic or lithic sandstone)

Fossilized Shark Tooth

Carcharocles sp. or Striatolamia sp. (Phosphate/Carbonate mineralized Hydroxyapatite)

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

Fossil brachiopod or bivalve shell

Indeterminate fossilized carbonate shell; likely a brachiopod (Phylum Brachiopoda)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Limestone (Weathered Aggregate)

Sedimentary Carbonate Rock (CaCO3)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Granite

Granite (Felsic Plutonic Rock)

Limestone with Chert Nodule

Carbonate rock (CaCO3) with Microcrystalline Silicon Dioxide (SiO2) inclusion

Iron-rich concretion or weathered ironstone

Limonite/goethite-rich iron oxide aggregate, commonly approximated as FeO(OH)·nH₂O

Basalt (Vesicular)

Basalt (Mafic volcanic rock)

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Black Tourmaline (Schorl)

Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)

Fossilized Bored Limestone

Limestone with Ichnofossils (Gastrochaenolites or Entobia)

Granite

Phaneritic plutonic rock (SiO2 range 70-75%)

Granite

Granite (Felsic Plutonic Rock)

Tumbled gray stone, likely quartzite or fine-grained basalt

Provisional identification: quartzite (mostly microcrystalline SiO₂) or basalt (plagioclase–pyroxene aggregate)

Likely milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Polished dark stone fragment, possibly slate or schist

Fine-grained foliated metamorphic rock; exact mineral composition is indeterminate from the image