Not A Rock Or Mineral

Weathered granitic boulder

Granite, typically composed of quartz, feldspar, and mica

Weathered greenstone (probable)

Chlorite–actinolite–epidote-rich metamorphosed mafic rock; exact identification requires testing

Greenstone pebble

Likely chlorite- and/or actinolite-bearing metamorphic rock; exact composition cannot be determined from the image.

Basalt with Granite Inclusions (Xenoliths)

Mafic igneous rock (Basalt) with Sialic minerals

Weathered granite or granitic gneiss

Granite; primarily quartz, feldspar, and mica

Small rounded pebble, likely quartz-rich river or beach stone

Unidentified lithic pebble; exact rock type cannot be determined from the image

Pegmatitic gneiss with a quartz–feldspar vein

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

Quartz Vein in Basalt or Mafic Rock

Silicon Dioxide (SiO2) vein in volcanic/mafic matrix

Red Sandstone

Sandstone (principally Quartz with Iron Oxide coating)

Granite

Felsic intrusive igneous rock

Milky quartz vein rock

Quartz (SiO₂), likely in a quartz-rich host rock with minor iron-stained minerals

Mixed rock fragments, likely iron-stained quartz-rich material

Indeterminate mixture; visible pale fragments may be quartz or feldspar, with iron-oxide staining (goethite/limonite)

Note: No specimen visible

Unidentified small mineral or rock fragment

Not identifiable from the image; the fragment may be a common silicate or other mineral grain.

Weathered granite

Granite, a quartz–feldspar–mica intrusive igneous rock

Basalt with Quartz Vein

Extrusive Igneous Rock with Silicon Dioxide Vein

Quartz Geode

Silicon Dioxide (SiO2)

Likely greenstone (metamorphosed basalt)

Metabasalt; commonly composed of chlorite, actinolite, epidote, and albite

Granite River Rock

Intrusive igneous rock (composed mainly of quartz, alkali feldspar, and plagioclase)

Small brown stone (indeterminate)

Unidentified; the image does not show enough detail for a reliable identification

Iron-rich breccia or weathered ironstone

Goethite–hematite-bearing limonite, possibly with quartz and altered rock fragments

Weathered greenstone pebble

Likely metabasalt (chlorite–actinolite-rich greenschist); exact identification requires close examination

Granite

Intrusive Igneous Rock

Sandstone

Sedimentary Clastic Rock

Sandstone

Clastic Sedimentary Rock

Sandstone

Sedimentary quartz arenite

Green Quartz

Silicon Dioxide (SiO2)

Sandstone

Sedimentary rock composed mainly of quartz sand-sized minerals

Sandstone (with Rock Art)

Sandstone (Clastic Sedimentary Rock)

Granodiorite (Weathered)

Granodiorite

Epidote

Calcium aluminum iron silicate hydroxide, Ca2(Al, Fe)3(SiO4)3(OH)

Greenstone, likely altered basalt

Metabasalt (chlorite–actinolite–epidote assemblage), likely greenschist-facies greenstone

Quartz Vein in Basalt or Slate

Hydrothermal quartz vein traversing mafic host rock

Gneiss

Foliated Metamorphic Rock (Gneiss)

Unidentified pale mineral or rock specimen

Indeterminate; image quality prevents reliable mineral identification

Sandstone

Sedimentary Rock (Quartzose Sandstone)

Sandstone (or Siltstone Concretion)

Arenite / Quartzose Sandstone

Sandstone

Clastic Sedimentary Rock

Sandstone

Sedimentary quartz arenite

Sandstone

Clastic Sedimentary Rock

Sandstone

Sedimentary rock composed mainly of quartz sand

Beach Pebble (Basalt/Porphyry)

Weathered Basalt or Porphyry