Metamorphic Rock (Composed Of Multiple Minerals)

Gravel / Crushed Stone

Aggregate (mixed mineral rock fragments)

Banded Gneiss

Banded Gneiss (Metamorphic Rock)

Slate

Slate; fine-grained metamorphosed shale, commonly composed of quartz, illite/muscovite, and chlorite

Granite

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

Likely blue-gray gneiss

Gneiss, a foliated metamorphic rock; exact mineral composition cannot be confirmed from the image

Light-colored quartzite pebble (tentative)

Quartzite, composed mainly of quartz (SiO₂)

Sandstone

Sedimentary rock composed mainly of sand-sized minerals or rock grains

Quartzite

Quartzite (composed primarily of Quartz, SiO2)

Botryoidal Chalcedony / Agate

Silicon Dioxide (SiO2)

Mica Schist

Mica Schist (composed mainly of Muscovite / Biotite, Quartz, and Feldspar)

Marble

Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).

Gneiss (Metamorphic Pebble)

Gneissic Metamorphic Rock

Gneiss (Granitic Gneiss)

Gneiss (composed primarily of Quartz, Feldspar, and Mica)

Quartz-rich granite (likely leucocratic granite)

Granite, composed mainly of quartz and feldspar with minor dark minerals

Greenstone (Amygdaloidal Basalt)

Amygdaloidal Basalt (frequently composed of Plagioclase Feldspar, Pyroxene, and Olivine with Chlorite inclusions)

Foliated Metamorphic Rock (likely Gneiss or Schist)

Gneissic Metamorphic Rock

Likely weathered mica-rich rock fragment

Probable schist, composed mainly of quartz, feldspar, and mica

Granite

Granite

Granite

Granite (composed primarily of Quartz, Feldspar, and Mica)

Quartzite

Quartzite (composed primarily of Quartz, SiO2)

Pegmatite (Granitic Pegmatite)

Pegmatite (Quartz + Potassium Feldspar + Mica)

Desert Varnish (on Sandstone)

Rock Varnish (composed of Manganese oxides, Iron oxides, and Clay minerals)

Coarse-grained granite (likely biotite granite)

Granite, composed mainly of quartz and feldspar with dark biotite or amphibole

Quartzite

Quartzite, composed predominantly of recrystallized quartz (SiO₂)

Sandstone Pebble

Sandstone (Quartzose/Feldspathic Sandstone)

Gneiss

Gneissic Metamorphic Rock

Dalmatian Stone

Dalmatian Jasper (a misnomer) / Perthitic Igneous Rock

Ironstone

Ferruginous Sedimentary Rock (composed of Goethite, Hematite, and Limonite)

Red Sandstone

Arenite (composed primarily of Quartz and Iron Oxide)

Weathered quartz-rich metamorphic rock

Likely quartzite or quartz-rich gneiss; exact identification requires a fresh surface and testing

Zircon

Zircon (ZrSiO4)

Vein-bearing sandstone or quartzite cobble

Quartz-rich sandstone with white quartz veins; possibly metamorphosed to quartzite

Granite Pebble

Intrusive Igneous Rock

Likely dark green-gray metamorphic pebble

Indeterminate; possibly chlorite schist, serpentinite, or amphibolite

Sandstone

Arenite

Sandstone

Arenite (SiO2 primarily)

Dalmatian Jasper

Dalmatian Stone (a microcrystalline quartz and feldspar rock with arfvedsonite)

Pegmatitic gneiss with a quartz–feldspar vein

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

Schist

Schist (metamorphic rock)

Dalmatian Stone (Dalmatian Jasper)

Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite

Biotite–quartz–feldspar gneiss

Gneiss, composed chiefly of quartz (SiO₂), feldspar, and dark mica, likely biotite

Likely slate

Slate; fine-grained rock composed mainly of quartz, mica and/or chlorite