Igneous, Metamorphic, And Sedimentary (Mixed Assemblage)

Mixed polished gemstone and mineral collection

Primarily quartz varieties (SiO₂), plus probable aventurine, rose quartz, amethyst, agate, jasper, serpentine, feldspar, and possibly dyed or man-made glass pieces

Assorted Tumbled Gemstones

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

Mixed pebble collection, including likely flint, quartzite, and fossil material

Varied silicate rocks; visible specimen may include chert (microcrystalline SiO₂), quartzite, and a possible fossil

Pegmatitic granite

Granite, quartz–feldspar–mica assemblage

Jasper and Basalt Pebble

Polymineralic lithic pebble

Red garnet-bearing metamorphic rock

Almandine garnet (Fe₃Al₂Si₃O₁₂), likely in mica schist or quartz-rich matrix

Biotite-rich granite or granitic gneiss

Granite; quartz–feldspar–biotite assemblage

Mixed mineral and rock collection, including likely amethyst and assorted tumbled stones

Unidentified mixed specimens; visible purple quartz is likely amethyst (SiO₂)

Mixed mineral and rock specimen collection

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

Colorless faceted gemstone, likely cubic zirconia

Synthetic cubic zirconia (zirconium dioxide, ZrO₂); identity is visual and not definitive

Green-and-gold apatite-bearing rock, possibly epidote skarn

Apatite-group mineral, commonly fluorapatite (Ca₅(PO₄)₃F), with probable epidote and quartz; exact identification requires testing

Fossil Assortment and Geological Specimens

Various (including Ammonoidea)

Serpentinite (probable)

Serpentinite, a rock composed chiefly of serpentine-group minerals such as antigorite, lizardite, or chrysotile

Pegmatitic granite (likely quartz–feldspar-rich rock)

Granitic pegmatite; chiefly quartz (SiO₂), feldspars, and mica

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.

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

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

Gravel and Sand Aggregate

Unconsolidated Clastic Sediment

Conglomeratic sandstone / breccia-like gravel rock

Polymictic conglomerate (possibly lithified gravel or concrete-like natural conglomerate)

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

Mixed Rock Assortment

Polylithic geological specimens

Likely quartz-bearing metamorphic pebble

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

Connemara Marble

Calcitic Marble / Serpentinite composite

Muscovite-rich mica schist

Mica schist, chiefly muscovite [KAl₂(AlSi₃O₁₀)(OH)₂], possibly with quartz and feldspar

River Pebbles (including Granite and Basalt)

Mixed Igneous Rocks (Granite, Basalt)

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

Granite with Pegmatite Dike

Felsic intrusive igneous rock

Weathered, foliated metamorphic rock (likely schist)

Mica schist, composition uncertain from the photograph

Epidote in Matrix (likely Amphibolite or Gneiss)

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

Mixed Pebbles and Shell Fragments

Polylithic sedimentary aggregate and biogenic calcium carbonate

Mixed river pebbles (gravel)

Polymictic alluvial gravel; diverse clasts, likely including quartz, feldspar-rich granitoids, and metamorphic rocks

Rounded, foliated metamorphic pebble (likely schist)

Mica schist, composition uncertain from the image

Mixed stream gravel and cobbles

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

Mixed River Pebbles (including Unakite and Jasper)

Polymineralic geological specimens

Gravel or Crushed Stone

Fragmented Aggregate Stone

Milky quartz rough chips

Quartz (silicon dioxide, SiO₂)

Weathered slate or phyllite

Foliated metamorphic rock, commonly quartz–mica–chlorite assemblage

Lichen-covered granite

Granite, chiefly quartz–feldspar–mica; surface colonized by lichens

Magnetite-rich iron ore

Magnetite (Fe₃O₄), possibly mixed with hematite or metallic sulfides

Mixed rounded gravel and weathered rock fragments

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

Mixed rough mineral specimens, likely quartz-bearing rocks

Probable quartz (SiO₂), with possible feldspar, iron oxides, and altered host rock

Jasper

Microcrystalline Quartz (SiO2)

Metallic sulfide-bearing ore, likely pyrite-rich rock

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