Sedimentary And Igneous (Mixed)

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

Garnet (likely Almandine, Pyrope, or a blend)

Garnet group minerals: X3Y2(SiO4)3, where X and Y represent various metal ions (e.g., Almandine: Fe3Al2(SiO4)3, Pyrope: Mg3Al2(SiO4)3)

Pyrite-bearing sulfide specimen

Pyrite (FeS₂), possibly with chalcopyrite (CuFeS₂) and/or marcasite

Metallic sulfide mineral specimen, likely pyrite

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

Black Tourmaline

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Tumbled labradorite beads

Labradorite, a calcium-rich plagioclase feldspar (approximately (Ca,Na)(Al,Si)₄O₈)

Copper-stained quartz/igneous rock specimen

Quartz (SiO₂), with secondary copper minerals; host likely altered volcanic rock

Concrete with Exposed Aggregate

Anthropogenic conglomerate (Concrete)

Tumbled hematite (likely hematite-rich iron oxide)

Hematite, Fe₂O₃; possibly mixed with magnetite, Fe₃O₄

Polished red jasper with quartz/chalcedony

Jasper (microcrystalline quartz, SiO₂), locally mixed with chalcedony or quartz

Mixed metamorphic rock fragments, likely garnet-bearing schist and quartzite

Quartz–feldspar–mica schist/quartzite; red grains may be almandine garnet

Lapis Lazuli

Lapis Lazuli (a rock composed primarily of Lazurite)

Likely granite or granitic gneiss

Coarse-grained quartz–feldspar–mica rock; possibly biotite granite or banded granitic gneiss

Concrete

Anthropogenic Sedimentary Conglomerate (Cement mixture: typically Ca2SiO4, Ca3SiO5, Ca3Al2O6)

Granite Pebble with Quartz/Feldspar Vein

Intrusive Felsic Igneous Rock (Granite)

Bauxite

Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)

Ironstone Concretion (Moqui Marble)

Iron Oxide Concretion (Fe2O3 / FeO(OH) mixed with SiO2)

Mixed rock fragments, likely granite and weathered metamorphic rock

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

Epidosite (Epidote-rich rock)

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

Black Tourmaline

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Tumbled pastel gemstone bead strand

Likely dyed or heat-treated quartz/chalcedony varieties, possibly rose quartz, amethyst, and agate

Hematite-rich ironstone concretion

Hematite (Fe₂O₃), likely mixed with goethite/limonite and silica

Granite

Granite (composed of quartz, potassium feldspar, plagioclase, and mica/biotite)

Yellow-brown jasper or silicified volcanic rock

Microcrystalline quartz (chalcedony), SiO₂, likely jasper

Botryoidal limonite/goethite nodule

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

Iron-rich ochre (red/brown hematite pigment)

Hematite, Fe₂O₃, likely mixed with clay and quartz grains

Clear Quartz

Silicon dioxide (SiO2)

Tumbled green jasper (probable serpentine-rich stone)

Jasper, microcrystalline quartz (SiO₂), possibly mixed with serpentine or chlorite

Tumbled jasper and agate assortment

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral impurities

Magnetite-rich black sand

Magnetite (Fe₃O₄), likely mixed with other heavy minerals

Metallic sulfide mineral specimen, likely pyrite

Pyrite (FeS₂), possibly mixed with marcasite or another iron sulfide

Pyrite-bearing sulfide ore (likely pyrite with iron oxides)

Pyrite, FeS₂, possibly mixed with limonite/goethite and other sulfides

Mixed rounded river pebbles, probably quartz-rich metamorphic and volcanic rocks

Predominantly quartzite/metachert, with possible rhyolite, sandstone, and iron-stained quartz; exact species cannot be determined confidently from the image

Magnetite sand (black iron-oxide sand)

Magnetite, Fe₃O₄; commonly mixed with ilmenite and other heavy minerals

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Iron-rich sulfide ore, likely pyrite-bearing gossan

Pyrite (FeS₂), possibly mixed with iron oxides/hydroxides and other sulfides

Natural gemstone and mineral collection

Mixed specimens, including turquoise, tiger’s eye, amethyst, fluorite, pyrite, garnet, rose quartz, lapis lazuli, obsidian, rhodonite, red corundum, labradorite, calcite, lepidolite, sodalite, apatite, and others

Amazonite (likely mixed with other feldspars/minerals)

Amazonite is a variety of Microcline, which is a tectosilicate mineral, formula KAISi3O8. The mixed beads could include other feldspars or quartz.

Pegmatite

Igneous Pegmatite (felsic intrusive rock)

Yellow-orange quartz (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂), colored by iron impurities or irradiation

Metallic sulfide ore, possibly pyrite-rich

Pyrite (FeS₂), potentially mixed with chalcopyrite, galena, or iron oxides

Metallic sulfide mineral specimen, likely pyrite

Pyrite (iron disulfide, FeS₂), possibly mixed with marcasite or chalcopyrite