Igneous, Sedimentary, And Metamorphic Mix

Aggregate Concrete

Anthropogenic Conglomerate (Technosol)

River Pebble (Gravel Pebble)

Stream-rounded Rock / Siliciclastic Pebble

Silty Sand / Loam

Unconsolidated Clastic Sediment (Silicon Dioxide / Alumino-silicates mixture)

Garnet (Red Garnet)

Garnet Group. The red varieties seen in jewelry are typically Almandine (Fe3Al2(SiO4)3), Pyrope (Mg3Al2(SiO4)3), or a mix of the two (pyrope-almandine series).

Likely schist, possibly serpentinite

Mica schist; potential chlorite–serpentine-rich metamorphic rock

Greywhacke (River Pebble)

Graywacke (immature sandstone)

Bumblebee Jasper (technically a type of Agate/Anhydrite)

Calcite and Anhydrite with inclusions of Realgar and Orpiment (As2S3)

River Cobble (Quartzite/Granite mix)

Quartzite-rich river stone

Asphalt / Road Aggregate

Bituminous Conglomerate (synthetic)

Porphyritic Igneous Rock / Basalt or Andesite Xenolith in Granite or Quartzite

Silicate rock with contrasting xenolith/inclusion

Puddingstone (Polished Pebble)

Conglomerate (Quartz-rich)

Greenish metamorphic rock (possibly chlorite schist)

Chlorite-rich schist; exact identification is uncertain from the image

Crushed Limestone

Sedimentary Calcite/Dolomite Rock (CaCO3)

Pyrite in Quartzite/Graphite Matrix

Iron Sulfide (FeS2)

Fancy Jasper

Jasper (Cryptocrystalline Quartz, SiO2)

Weathered granite

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

Quartz

Silicon Dioxide (SiO2)

Pyrite in Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)

Diorite

Intrusive Igneous Rock (Intermediate Composition)

Asphalt (Bituminous Concrete)

Bituminous Concrete / Pavement

Zebra Jasper (usually a trade name for Serpentine or Basalt blend)

Antigorite/Chrysotile (Serpentine family) - Mg3Si2O5(OH)4

Tiger's Eye (Blue/Golden mix)

Pseudomorph of Quartz after Crocidolite (SiO2)

Concrete / Conglomerate (Man-made)

Artificial Conglomerate (Cementitious Composite)

Pumice

Pumice (a vesicular volcanic glass)

Greywacke

Lithic Sandstone

Tumbled cream-colored stone, possibly quartz or calcite

Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Jasper and Basalt (Mixed Breccia or Chert)

Silicon Dioxide (SiO2) with Ferromagnesian silicates

Concrete or artificial stone core sample

Artificial conglomerate

Diorite

Diorite (Intermediate intrusive igneous rock)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Quartz Mix and Feldspar Group

Silicon Dioxide (SiO2) and Potassium Alumino-silicates (KAlSi3O8)

Porphyritic granite (granite porphyry)

Quartz–feldspar porphyritic granite; mainly quartz, K-feldspar, plagioclase, and biotite/hornblende

Tumbled tan pebble

Likely quartz-rich sandstone or chert; exact identification requires testing

Agate (Carnelian-Blue Agate mix)

Silicon Dioxide (SiO2)

Chalcedony (Jasper/Agate mix)

Quartz (microcrystalline SiO2)

Chalcedony (Agate/Jasper mix in host rock)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Granite

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

White quartz bead strand

Quartz, silicon dioxide (SiO₂), likely milky or translucent quartz; beads are polished and drilled

Tumbled yellow-brown stone, likely quartzite or chalcedony

Quartz-rich rock; predominantly microcrystalline quartz (SiO₂), identification uncertain from image alone

Sandstone-based Concrete Fragment

Cementitious Composite with Sedimentary Aggregate

River Cobbles (Basalt, Quartzite, and Sandstone mix)

Fluvial detritus (primarily SiO2, Plagioclase, and Pyroxene mix)

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2) with iron oxide inclusions