Sedimentary And Igneous (Mixed)

Mixed rounded rock pebbles

Likely granitic gneiss, basaltic rock, and quartz-rich granitic material; exact identification is uncertain from the image

Mixed rock and mineral gravel

Predominantly granite/granodiorite, basaltic rocks, quartz, and possible gneiss; exact identification is uncertain from the image

Jasper and Quartz Pebble

Silicon dioxide (SiO2) microcrystalline quartz variety

Mixed collection of polished geological specimens; central specimen is likely diorite

Diorite (probable; plagioclase feldspar and dark amphibole/biotite)

Snowflake Obsidian (possibly mixed with Jasper or other matrix)

Obsidian with Cristobalite inclusions

Mixed landscaping gravel with a pink granite cobble

Primarily granite (quartz, alkali feldspar, plagioclase, biotite); mixed pebble assemblage

Mixed rounded stream pebbles

Most appear to be granitic and mafic igneous rocks, including granite, gneiss, basalt, and possibly quartzite; exact identification is uncertain from the image.

Sandstone and Mixed Rock Assemblage

Clastic Sedimentary Rock / Quartz Arenite

Conglomerate

Conglomerate (Sedimentary Clastic Rock)

Weathered iron-stained rock fragment

Uncertain from the image; likely an iron-oxide-stained, quartz- and feldspar-bearing rock

Pegmatitic granite

Quartz–feldspar–mica granite pegmatite

Rounded weathered stone, likely basaltic or volcanic rock

Indeterminate fine-grained mafic volcanic rock; possibly basalt or andesite

Quartz with Feldspar

Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)

Graywacke

Graywacke Sandstone

Leopard Skin Jasper

Silicon Dioxide (SiO2) with mineral inclusions

Greywacke

Lithic Sandstone (Greywacke)

Polished/tumbled metallic sulfide specimen, likely pyrite

Pyrite (FeS₂), possibly mixed with chalcopyrite or other sulfides

Assorted gemstone jewelry

Mixed natural and synthetic gemstone cabochons and faceted stones; individual species cannot be determined reliably from this image

Garnet, likely almandine–spessartine

Garnet-group nesosilicate; commonly almandine Fe₃Al₂(SiO₄)₃ or spessartine Mn₃Al₂(SiO₄)₃

Mixed rounded gravel and pebbles

Polymictic clasts, likely including granite, basalt, quartzite, sandstone, and schist

Polymictic conglomerate

Lithified polymictic conglomerate; clasts likely quartzite, granite, and volcanic rock in a dark matrix

Bauxite (Iron-stained Chert / Ironstone Aggregate)

Hydrous aluminum oxide mixture (mainly Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Goethite α-Fe3+O(OH))

Yellow Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Devil's Toenail (Fossil Oyster)

Gryphaea arcuata (Calcium Carbonate, CaCO3)

Weathered polymictic rock fragment, likely granite-rich conglomerate

Indeterminate mixed lithology; apparent granitic clasts containing quartz, feldspar, and dark mafic minerals

Polished brown jasper

Jasper (microcrystalline quartz, SiO₂), likely iron-oxide-rich variety

Epidote in Matrix (Unakite-like Rock Fragment)

Epidote (Ca2(Al,Fe)3(SiO4)3(OH)) / Altered Metamorphic Pebble

Olivine in Quartz/Feldspar Matrix (Peridotite or Granitic Pegmatite)

(Mg,Fe)2SiO4 (Olivine) with Quartz / Feldspar

Chakra Stone Bracelet

Mixed Mineral Assembly (Scoria, Amethyst, Lapis Lazuli, Turquoise/Howlite, Impression Jasper, Tiger's Eye, Carnelian, Red Jasper)

Epidosite

Epidosite (composed primarily of Epidote and Quartz)

Vesuvianite (Idocrase)

Vesuvianite, Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4

Chalcedony Agate / Carnelian nodules in Matrix

SiO2 (Silicon Dioxide) with iron oxide inclusions

Pink granite (likely weathered granite)

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

Polished black stone, likely obsidian or dark basalt

Volcanic glass (obsidian), possibly basalt; exact identification requires testing

Rounded, weathered rock (likely quartz-rich granite or gneiss)

Undetermined quartz–feldspar-rich rock; precise identification requires closer examination

Granite pebble

Granite, chiefly quartz, potassium feldspar, and plagioclase, with dark biotite or amphibole

Porphyritic granite pebble

Granite, chiefly quartz (SiO₂), alkali feldspar and plagioclase, with minor biotite/hornblende

Granitic Quartz or Pegmatite

Quartz with Orthoclase Feldspar (SiO2 + KAlSi3O8)

Asphalt Concrete

Bituminous Concrete (Anthropic Rock)

Chert Pebble

Chert (Microcrystalline Quartz, SiO2)

Pyrite in Matrix (Healers Gold / Pyrite Egg)

Iron Disulfide (FeS2) with Magnetite/Hematite matrix

Pyrite-bearing sulfide specimen (likely pyrite)

Pyrite, FeS₂; possibly mixed with pyrrhotite or chalcopyrite