Igneous, Metamorphic, And Sedimentary (Mixed Assemblage)

Polished/tumbled metallic sulfide specimen, likely pyrite

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

Mixed Tumbled Stones Collection

Mixed Silicates and Carbonates (Quartz, Amorphous Silica, Carbonates)

Likely quartz-bearing metamorphic pebble

Indeterminate; probable quartzite or quartz-rich gneiss with dark mica/amphibole

Pyrite-bearing sulfide ore

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

Gravel and Sand Aggregate

Unconsolidated Clastic Sediment

Epidote in Matrix (likely Amphibolite or Gneiss)

Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Metamorphic Matrix

Fossil Assortment and Geological Specimens

Various (including Ammonoidea)

Gravel or Crushed Stone

Fragmented Aggregate Stone

Biotite-rich granite or granitic gneiss

Granite; quartz–feldspar–biotite assemblage

Mixed mineral and rock specimen collection

Assorted silicates, carbonates, oxides, and sulfides; individual species cannot be reliably identified from this image

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.

Milky quartz rough chips

Quartz (silicon dioxide, SiO₂)

Mixed rounded gravel and weathered rock fragments

Polymictic alluvial or glacial gravel; composition appears to include basaltic, quartz-rich, and feldspathic clasts

Mixed stream gravel and cobbles

Polylithic alluvial deposit; individual clasts are not identifiable at this resolution

Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles

Mixed gemstones (primarily Silicon Dioxide - SiO2)

Assorted Tumbled Gemstones

Mixed oxides and silicates (including Quartz, Chalcedony, and Feldspar variants)

Mixed polished and tumbled mineral specimens, prominently amethyst

Amethyst: purple quartz, SiO₂; accompanying pieces may include jasper, agate, aventurine, tiger’s eye, and other lapidary stones

Basalt with Xenolith

Extrusive Igneous Rock containing Mantle Xenolith

Sodalite

Na8Al6Si6O24Cl2

Mixed mineral and rock specimen collection with an obsidian-like centerpiece

Likely black obsidian (volcanic glass), alongside quartz, amethyst, agate/jasper, and other tumbled minerals

Metallic sulfide mineral specimen, likely pyrite

Pyrite (FeS₂), possibly a pyrite-rich sulfide aggregate

Red Jasper with Quartz Veining

Microcrystalline Quartz (SiO2)

Epidosite (Epidote-rich rock)

Epidosite (consisting primarily of Epidote: {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH))

Biotite-bearing metamorphic rock, likely schist

Mica schist; quartz–feldspar–biotite assemblage

River Pebbles (including Granite and Basalt)

Mixed Igneous Rocks (Granite, Basalt)

Mixed river gravel (alluvial conglomeratic sediment)

Polymictic alluvium; composition includes quartz, feldspar, chert, granite, basalt, and metamorphic rock fragments

Limestone and Quartz Gravel with Petrified Wood

Sedimentary gravel aggregate and fossilized wood

Quartz

Silicon dioxide (SiO2)

Mixed rounded river pebbles, likely basalt and granite

Basalt (fine-grained mafic rock) and granite/granitoid (quartz–feldspar rock)

Mixed River Pebbles (including Unakite and Jasper)

Polymineralic geological specimens

Mixed Gemstone Collection

SiO2 (Quartz varieties) and Biogenic CaCO3 (Nacre)

Clear Quartz

Silicon Dioxide (SiO2)

Graphite

Graphite (Carbon, C)

Mixed rock fragments, likely granite and weathered metamorphic rock

Granite (quartz–feldspar–mica aggregate) with probable schist/gneiss fragments

Quartz

Silicon Dioxide (SiO2)

Rhodonite

Rhodonite (Mn,Fe,Mg,Ca)SiO3

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Milky Quartz with Nephrite Jade

Silicon Dioxide (SiO2) with Ca2(Mg,Fe)5Si8O22(OH)2

Granite

Coarse-grained felsic intrusive igneous rock; primarily quartz, alkali feldspar, plagioclase, and biotite/hornblende

Dark gray weathered pebble, likely basalt

Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides

Granite Thin Section

Granitic rock (Phaneritic texture)

River Rock

Mixed lithology clast