Sedimentary Rock (Possibly A Conglomerate Or Coarse Grained Sandstone)

Breccia Pebble

Sedimentary Breccia

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Weathered rock pebble, possibly sandstone

Likely quartz-rich sandstone; precise identification requires closer examination

Tan chert or fine-grained sandstone fragment

Microcrystalline quartz (SiO₂), possibly chalcedony-rich chert

Rounded brown river pebble

Indeterminate lithic clast; possibly weathered sandstone or fine-grained volcanic rock

Feldspar-rich granite or granitic gneiss

Granite; mainly quartz (SiO₂), feldspar, and mica

Sandstone

Sandstone (composed predominantly of Quartz, SiO2, with Feldspar and Clay minerals)

Conglomerate

Polymictic conglomerate; rounded clasts cemented in a fine-grained matrix

Puddingstone (Polished Pebble)

Conglomerate (Quartz-rich)

Concrete or artificial stone core sample

Artificial conglomerate

Jasper Conglomerate (specifically Puddingstone)

Jasper Conglomerate (Siliceous sedimentary rock)

Weathered quartz-rich metamorphic rock, likely quartzite

Quartzite (mostly SiO₂), possibly ferruginous mica-bearing quartzite

Conglomerate (possibly breccia)

Clastic sedimentary rock; chiefly quartz- and feldspar-rich clasts in a weathered iron-oxide cement

Granite fragment

Granite; chiefly quartz, alkali feldspar, and plagioclase, with minor mica or amphibole

Puddingstone (Quartzite Pebble)

Metaconglomerate / Jasper-Quartzite Pebble

Conglomerate

Clastic Sedimentary Conglomerate

Conglomerate

Clastic sedimentary conglomerate

Weathered quartz-rich rock, likely sandstone or quartzite

Quartz sandstone (possibly weakly metamorphosed quartzite); predominantly SiO₂

Quartz-rich rock, likely quartzite or weathered sandstone

Quartzite (mostly SiO₂); possibly quartz arenite sandstone

Tumbled tan stone, possibly sandstone or weathered limestone

Indeterminate; likely quartz-rich sandstone or calcitic limestone

Iron-rich rock, possibly ironstone

Likely ferruginous sandstone or ironstone; exact identification requires testing

Weathered sandstone or iron-stained quartzite

Quartz-rich sandstone; possibly weakly metamorphosed quartzite (SiO₂-dominant)

Conglomerate (Asphaltic/Anthropogenic)

Clastic sedimentary rock / Bituminous mixture

Greenish-gray quartz-rich rock, possibly weathered granite or quartzite

Provisional identification: quartz–feldspar aggregate; exact species cannot be confirmed from one photograph

Likely weathered sandstone or iron-rich sedimentary rock

Quartz-rich sandstone, possibly ferruginous sandstone

Sandstone (with possibly iron oxides and other minerals)

Sandstone

Likely weathered sandstone or iron-stained sedimentary pebble

Indeterminate clastic sedimentary rock; possibly quartz-rich sandstone

Weathered quartz-bearing rock, possibly sandstone or quartzite

Provisional: quartzite (mostly SiO₂); could alternatively be iron-stained quartz sandstone

Brecciated rock, likely polymict breccia

Polymict breccia; exact lithology cannot be determined from the image

Banded sandstone

Quartz-rich sandstone (quartz arenite or feldspathic sandstone; exact type cannot be determined from the image)

Concrete with Aggregate

Artificial Conglomerate (Cement and Aggregate)

Quartz Pebble / River Silt Grain

Silicon Dioxide (SiO2)

Weathered sandstone or iron-rich sedimentary rock

Quartz-rich arenite, possibly ferruginous sandstone

Unidentified orange-brown rock fragment

Likely weathered iron-rich volcanic rock or ochre-bearing material; exact identification is impossible from the blurred image

Sandstone (Common Quartz Pebble/Rock)

Sedimentary rock / Quartz arenite

Quartz-rich sandstone

Quartz arenite (likely); predominantly SiO₂ grains cemented by silica, calcite, or iron oxides

Weathered sandstone or quartzite cobble

Quartz-rich sandstone; possibly metamorphosed to quartzite

Metaconglomerate

Metaconglomerate (Quartzite conglomerate)

Iron-stained breccia or weathered conglomerate pebble

Clastic sedimentary rock; likely quartz-rich sandstone/breccia with dark mafic or iron-manganese fragments

Gneiss

Foliated Metamorphic Rock

Quartz-rich metamorphic rock, likely quartzite

Quartzite (mostly crystalline SiO₂), possibly quartz-rich schist or vein quartz

Siltstone

Siltstone (Clastic Sedimentary Rock)