Sedimentary Or Igneous (Secondary Formation)

Milky Quartz

Silicon Dioxide (SiO2)

Rough Agate/Chert Nodules

Cryptocrystalline Quartz (SiO2)

Banded Gneiss / Metamorphic River Pebble

Gneiss (Foliated Metamorphic Rock)

Banded Gneiss Pebble

Gneiss (Metamorphic Rock)

Banded Calcite (often sold as Mexican Onyx)

Calcium Carbonate (CaCO3)

Chert (with Quartz vein)

Chert (Silicon Dioxide, SiO2)

Weathered iron-rich rock (likely ironstone or altered basalt)

Probable limonite/goethite-bearing basalt or ironstone; exact identification requires testing

Blue Calcite Sphere

Calcium Carbonate (CaCO3)

Blue Calcite (commonly sold as Caribbean Calcite)

Calcium Carbonate (CaCO3)

Blue Calcite

Calcium Carbonate (CaCO3)

Pink Calcite (Mangano Calcite)

Calcium Carbonate (CaCO3)

Diamond Druzy (Crystalline Diamond)

Carbon (C)

Gold Nugget

Native Gold (Au)

Iron-stained Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

River Pebbles (Basalt and Graywacke/Limestone)

Mafic Volcanic Rock / Impure Sandstone

Blue-green mineral specimen, likely chrysocolla or turquoise

Chrysocolla: hydrated copper phyllosilicate, approximately Cu₂H₂O₅Si; Turquoise: CuAl₆(PO₄)₄(OH)₈·4H₂O

Quartzite with Hematite staining

Quartzite (SiO2) with iron oxide inclusions

Carnelian Agate

Chalcedony (Silicon Dioxide, SiO2)

Weathered granitic rock

Granite, chiefly quartz + feldspar + mica; possibly a pale granodiorite

Botryoidal limonite/goethite nodule

Limonite (largely goethite, FeO(OH), with hydrated iron oxides)

Labradorite-bearing gneiss or altered feldspathic rock

Plagioclase-rich gneiss, locally labradorescent; composition likely plagioclase feldspar, quartz, mica, and iron-oxide veining

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Small white quartz fragment

Quartz (silicon dioxide, SiO₂)

Vesicular basalt (lava rock)

Vesicular basalt, composed mainly of plagioclase, pyroxene, and often olivine

Likely weathered quartz-rich rock fragment

Uncertain; possibly quartz-bearing granitic or metamorphic material (SiO₂-dominant)

Clear Quartz

Silicon Dioxide (SiO2)

Magnetite (Lodestone variety)

Magnetite (Fe3O4)

Magnetite / Hematite rich ore

Magnetite (Fe3O4) or Hematite (Fe2O3)

Raw Agate (Chalcedony Nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Milky or Iron-Stained Quartz

Quartz (Silicon Dioxide, SiO2)

Magnetite-rich ironstone (probable magnetite ore)

Magnetite, Fe₃O₄, likely in a fine-grained ironstone matrix

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Rounded metamorphic pebble, likely mica schist or gneiss

Mica schist/gneiss; commonly quartz, feldspar, and biotite or muscovite mica

Limestone

Calcium Carbonate (CaCO3)

Weathered metamorphic rock, likely mica schist or gneiss

Quartz–feldspar–mica schist/gneiss; exact identification is uncertain from the photograph

Seashell (Calcium Carbonate)

Calcium Carbonate (CaCO3)

Quartz (Milky Quartz / Quartzite)

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Malachite

Cu2CO3(OH)2 (Copper carbonate hydroxide)

Silver-colored mica schist

Muscovite–quartz schist, possibly with biotite