Man Made Rock (Technosol)

Granite

Granite (Felsic Plutonic Rock)

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Epidote

Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Quartz (Milky or Cloudy variety)

Silicon Dioxide (SiO2)

Picture Jasper

Silicon Dioxide (SiO2)

River Pebbles (Stream-rounded rocks)

Fluvial Detritus (varied mineralogy)

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Blue Howlite (Dyed)

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)

Jasper Breccia

Silicon Dioxide (SiO2) with impurities

Coquina Jasper

Fossiliferous Chalcedony (SiO2)

Labradorite (Larvikite variety)

Plagioclase Feldspar (Na,Ca)(Al,Si)4O8 with Monzonite/Syenite matrix

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Milky Quartz

Silicon Dioxide (SiO2)

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Sand Dollar Fossil

Echinoidea (Clypeasteroida)

Ironstone Concretion

Limonitic/Hematitic Concretion

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Bumblebee Jasper

Volcanic Tuff (mixture of Quartz, Sulfur, Hematite, and Orpiment)

Coral Fossil (Favosites type)

Phylum Cnidaria, Class Anthozoa (often CaCO3 - Calcium Carbonate)

Quartz with Limonite Staining

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)

Garnet in Matrix (Eclogite)

Eclogite, featuring Almandine or Pyrope Garnet [X3Y2(SiO4)3]

Dyed Agate

Chalcedony (Silicon Dioxide, SiO2)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock including secondary mineral infills)

Sandstone Concretion

Clastic Sedimentary Concretion (primarily SiO2 with Fe2O3 cement)

Chert (specifically Jasper)

Silicon dioxide (SiO2) with iron oxide inclusions

Unakite

Epidotized Granite

Amethyst (Agate/Chalcedony variety)

Silicon Dioxide (SiO2) with iron impurities

Pumice (likely)

Pumice (extrusive igneous rock)

Gneiss (High-grade Metamorphic Rock)

Gneiss (Metamorphic silicate rock)

Porphyritic Andesite

Porphyritic intermediate volcanic rock (Andesite)

Ferruginous Sandstone

Ferruginous Clastic Sedimentary Rock

Diorite

Phaneritic Intrusive Igneous Rock (Intermediate Composition)

Basalt

Basalt (extrusive igneous rock)

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)

Granite

Phaneritic Acidic Igneous Rock (Granite Group)

Sandstone (likely Fossiliferous)

Arenite / Sedimentum arenaceum

Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)

Chert (microcrystalline quartz)

Carnelian

Carnelian (SiO2)

Limestone

Calcium Carbonate (CaCO3)