Sedimentary Rock (Possibly A Conglomerate Or Coarse Grained Sandstone)

Graywacke

Lithic Sandstone (Graywacke)

Weathered sandstone or iron-stained sedimentary rock

Quartz-rich sandstone, possibly ferruginous sandstone

Weathered sandstone or iron-rich sedimentary rock

Indeterminate siliciclastic sandstone, possibly ferruginous sandstone

Gneiss

Gneiss (Metamorphic Rock)

Unidentified brown rock fragment

Likely iron-stained sandstone or weathered conglomeratic rock; species cannot be confirmed from the image

Weathered river cobble, possibly sandstone or volcanic tuff

Indeterminate lithology; likely fine-grained sandstone/siltstone, with possible iron-oxide veining

Conglomerate

Conglomerate

Rounded sandstone pebble

Quartz-rich sandstone, possibly iron-stained litharenite

Conglomerate

Clastic Sedimentary Rock

Rounded brown river pebble

Indeterminate lithic fragment; possibly weathered sandstone, mudstone, or basalt

Weathered iron-rich rock (possibly ironstone)

Likely ferruginous sandstone or ironstone; exact identification requires examination

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly crystalline SiO₂, possibly with feldspar and mica impurities

Jasper Conglomerate

Polymictic Conglomerate with Jasper and Quartz

Pink granite (probable)

Granite; primarily quartz, potassium feldspar, plagioclase, and minor mica

Conglomerate

Clastic sedimentary rock (Polymict conglomerate with quartz/calcite matrix)

Concrete / Conglomerate (Man-made)

Artificial Conglomerate (Cementitious Composite)

Likely weathered sandstone or metasandstone

Quartz-rich sandstone (possibly weakly metamorphosed metasandstone)

River Pebbles (Chert and Quartzite)

Sedimentary Clastic Rock (Silica-rich)

Weathered sandstone block

Quartz-rich sandstone, likely arkose or calcareous sandstone

Sandstone

Sandstone (composed primarily of sand-sized minerals or rock grains)

Conglomeratic volcanic breccia

Lithic volcanic breccia, likely andesitic or basaltic

Rounded conglomeratic river pebble

Polymict conglomerate (lithified gravel), composition uncertain from image

Weathered granite or granitic gneiss block

Granite, chiefly quartz, feldspar, and mica; possibly gneiss if the visible banding is structural

Conglomerate (Pebble Conglomerate)

Conglomerate

Weathered quartz-rich rock, possibly sandstone or quartzite

Indeterminate; likely quartz sandstone (SiO₂-rich), possibly weakly metamorphosed quartzite

Rounded sandstone pebble

Clastic sandstone, likely quartz–feldspar-rich (exact identification requires testing)

Gneiss

Gneiss (High-grade metamorphic rock)

Conglomerate

Conglomerate

Small weathered rock fragment

Indeterminate; possibly carbonate-rich sandstone or limestone

Rounded river pebble, likely fine-grained sandstone or siltstone

Indeterminate clastic sedimentary rock; possibly quartz-rich sandstone

Ferruginous Sandstone

Sandstone, Iron-rich

Conglomerate

Conglomerate rock

Brecciated polymictic rock, possibly impact breccia

Polymictic breccia; exact lithology indeterminate from image

Fossiliferous Sandstone / Fossil Fragment

Fossiliferous Sedimentary Matrix with Indeterminate Fossil Material

Granite / Arkosic Sandstone (Coarse Igneous or Sedimentary Aggregate)

Granite / Quartz-Feldspar Aggregate

Weathered brown rock fragment

Indeterminate; possibly iron-stained sandstone, mudstone, or weathered limestone

Weathered iron-rich rock (possibly ironstone)

Indeterminate ferruginous rock; likely iron-oxide-cemented sandstone or ironstone

Likely weathered sandstone or limestone pebble

Indeterminate sedimentary rock; possibly quartz-rich sandstone or calcitic limestone

Weathered conglomerate pebble

Polymictic conglomerate, likely quartz- and feldspar-rich clasts in a cemented matrix

Conglomerate (rounded-pebble rock)

Lithified polymictic conglomerate; clasts cemented by a finer mineral matrix

Pink feldspar-rich granite or pegmatite

Potassium-feldspar granite; chiefly microcline/orthoclase (KAlSi₃O₈), quartz, and minor mica

Rounded quartz-rich pebble, likely sandstone or granitic-derived pebble

Indeterminate clastic rock; likely quartz-rich sandstone/conglomerate clast