Mixed

Chrysocolla

Hydrated copper silicate, (Cu,Al)2H2Si2O5(OH)4·nH2O

Mixed rounded river pebbles

Polymictic gravel; individual clasts likely include quartzite, granite, and other common rocks

Weathered rock pebble, possibly sandstone

Likely quartz-rich sandstone; precise identification requires closer examination

Mixed river pebbles, likely including quartz-rich rocks

Unidentified mixed lithologies; the pale pieces appear quartz- or feldspar-rich, but the image is insufficient for a specific identification

Assorted small mineral and rock specimens

Indeterminate from the photograph; specimens may include turquoise-colored material, quartz/chalcedony, and assorted rocks

Road-surface aggregate (crushed stone)

Unidentifiable mixed lithic aggregate; likely basaltic/andesitic fragments with feldspar, quartz, and weathered rock

Engineered Quartz Stone

Agglomerated Quartz (SiO2 + Polymer Resin)

Unakite (or Epidote-rich Granite)

Unakite (Metamorphosed Granite consisting of Epidote, Orthoclase, and Quartz)

Pink Granite

Granite (Felsic Plutonic Rock)

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions (SiO2 + Fe2O3)

Ironstone concretion (possibly pyrite-bearing)

Iron-rich sedimentary concretion, likely composed of goethite/limonite with possible pyrite

Rounded river gravel (mixed alluvial pebbles)

Polymictic alluvial gravel; commonly composed of quartzite, granite, basalt, sandstone, and quartz

Quartz pebble in concrete

Quartz (SiO₂), embedded in Portland-cement concrete

Cobalt Blue Glass / Cullet Glass

Silicon dioxide (Amorphous man-made glass)

Asphalt Concrete

Bituminous conglomerate

Lapis Lazuli

Lapis Lazuli (contains lazurite, calcite, pyrite)

Asphalt Concrete

Bituminous Concrete / Asphaltic Composite

Caribbean Calcite

Calcite (CaCO3) with Aragonite (CaCO3)

Azurite and Malachite

Cu3(CO3)2(OH)2 (Azurite) / Cu2CO3(OH)2 (Malachite)

Mookaite Jasper

Silicified Radiolarite (SiO2 with iron impurities)

Chrysocolla in Matrix

Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O

African Jade

Grossular Garnet in massive rock matrix

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz (SiO₂), commonly called orbicular jasper or ocean jasper

Polymictic conglomerate or breccia (possibly concrete-like aggregate)

Lithified polymictic gravel; clasts may include basalt, granite, quartzite, and other silicates

Iron-rich concretion or weathered ironstone

Goethite–hematite-rich limonite (FeO(OH)·nH₂O / Fe₂O₃)

Concrete with Aggregate

Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)

Concrete rubble

Anthropogenic conglomerate

Gravel (mixed crushed stone)

Unidentified aggregate of crushed natural rock fragments

Jasper and Quartz

Silicon Dioxide (SiO2)

Jasper / Agate

Silicon dioxide (SiO2)

Mixed stream-worn rocks, likely including quartz-rich gravel

Composition indeterminate; visible material may include quartz (SiO₂) and assorted lithic fragments

Tumbled feldspar-rich granite

Granite, composed mainly of quartz and feldspar with dark biotite or amphibole

Feldspar-Quartz Rock (likely Pegmatite or Granite)

Feldspar-Quartz composite rock (KAlSi3O8 - SiO2)

Unakite

Unakite (altered granite)

Granite Pebble

Granite (composed of Quartz, Feldspar, and Mica)

Unakite

Epidotized Granite

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Polished Jasper Cabochons

Microcrystalline quartz (SiO2)

Mixed Gemstone and Mineral Collection

Mixed Silica and Carbonate minerals (SiO2, CaSO4·2H2O, etc.)

Costume Jewelry Gemstones (Emerald-imitation and semi-precious beads)

BeCuAl6Si6O18 (Beryl structure), frequently simulated by glass or synthetic spinel

Mixed river gravel (likely alluvial sediment)

Unconsolidated polymictic gravel; rock fragments of varied composition

Concrete fragment with Aggregate

Anthropogenic Concrete with Calcarious and Siliceous Aggregate