Mineral

Quartz Pebbles

Silicon Dioxide (SiO2)

Dark rock/mineral fragment

Undetermined; possibly magnetite-rich basalt or iron sulfide

Unidentified metallic mineral fragment

Indeterminate; possibly galena, hematite, or a metallic meteorite fragment

Small metallic mineral fragment

Indeterminate; possibly galena, hematite, magnetite, or metallic meteorite fragment

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2 with mineral cement)

Schist

Schist (Metamorphic Rock)

Fossilized tooth, likely mammalian molar

Silicified or mineral-replaced mammalian tooth; exact taxon cannot be determined from the image

Fossil Shell (Bivalve)

Class Bivalvia (fossilized)

Likely schist, possibly serpentinite

Mica schist; potential chlorite–serpentine-rich metamorphic rock

Fluorite

Fluorite (Calcium Fluoride, CaF2)

Sandstone

Arenite (SiO2 based with various mineral cements)

Weathered granitic rock fragment

Granitoid, likely granodiorite or granite

Schist

Mica schist, likely muscovite–biotite schist with quartz and feldspar

Fossilized Stingray Mouth Plate

Myliobatidae gen. et sp. indet. (e.g., Myliobatis, Aetobatus)

Unakite

Altered Granite (Epidotized Granite)

Vesicular volcanic rock, likely scoria

Scoria; composition commonly basaltic to andesitic, rich in plagioclase and pyroxene

Granite Glacial Erratic

Intrusive Phaneritic Felsic Rock (Granite)

Greenschist (Chlorite Schist)

Greenschist (Metamorphic rock dominated by chlorite, actinolite, and epidote)

Mica Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

Iron-stained Quartz

Silicon Dioxide with Limonite (SiO2 + FeO(OH)·nH2O)

Gneiss

Gneiss

Gneiss (with iron staining)

Gneiss

Gabbro

Gabbro (Mafic Plutonic Rock)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss (Metamorphic Rock)

Gneiss

Granite (Dioritic variant)

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

Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss (specifically a Granitic Gneiss)

Gneiss (Composition: Quartz, Feldspar, Mica)

Limonite Nodule

FeO(OH)·nH2O (Hydrated iron oxide-hydroxide)

Boxwork Siderite or Sepatarian Nodule Weathering

Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment

Native Copper

Native Copper (Cu)

Limonite (Iron Ore)

FeO(OH)·nH2O

Amygdaloidal Basalt

Extrusive Igneous Rock with Amygdules

Banded gneiss

Gneiss, commonly quartz–feldspar–biotite gneiss

Weathered granite or granitic gneiss

Granite: quartz + feldspar + biotite/hornblende; possible gneissic equivalent

Diorite (River Rock/Cobble)

Intermediate Plutonic Igneous Rock (Diorite)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Banded Gneiss

Gneiss

Diorite

Diorite (Intermediate intrusive igneous rock)

Diorite

Phaneritic intermediate plutonic rock

Fossilized bone or tooth fragment

Indeterminate fossil bone; possibly mammalian or reptilian

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)