All rocks & minerals

Fossil shark tooth

Shark tooth fossil; likely a fossilized lamniform shark tooth, identification uncertain from the photo

Navajo Sandstone

Navajo Sandstone (primarily quartz arenite)

Granite (likely)

Granite, a quartz–feldspar–mica intrusive igneous rock

Sodalite-bearing rock fragment (possibly sodalite in matrix)

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂; exact specimen uncertain from the image

Strawberry Quartz (Aventurine Quartz)

Silicon dioxide with hematite/goethite inclusions (SiO2)

Tumbled green fluorite

Fluorite (calcium fluoride, CaF₂)

Quartz-rich granite (small fragment)

Granite, a coarse-grained felsic intrusive igneous rock composed chiefly of quartz and feldspar, with possible mica

Weathered granite pebble

Granite, composed mainly of quartz, feldspar, and mica

Likely honey calcite (rough calcite)

Calcite, CaCO₃

Likely serpentinite (serpentine-rich rock)

Serpentinite, composed mainly of serpentine-group minerals (lizardite, antigorite, or chrysotile); identification from the photo is tentative.

Quartz-rich rock, possibly milky quartz or quartzite

Predominantly quartz (SiO₂); exact identification is uncertain from the image

Quartz-rich metamorphic rock (likely quartzite)

Quartzite, composed predominantly of quartz (SiO₂)

Quartz-rich pegmatite

Granitic pegmatite, composed chiefly of quartz (SiO₂) and feldspar, with possible mica

Operculum (Cat's Eye Shell)

Biogenic Aragonite/Calcite (CaCO3)

Polished picture jasper (likely)

Microcrystalline quartz (SiO₂), colored by iron oxides and other mineral impurities

Polished ocean jasper (orbicular jasper)

Microcrystalline quartz, chiefly SiO₂; commonly sold as ocean jasper

Polished sodalite

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂

Likely galena-bearing rock

Galena (lead sulfide, PbS), in a gangue rock that may include quartz or other sulfides

Leopard-skin jasper (likely polished jasper pebble)

Jasper, an opaque microcrystalline variety of quartz (SiO₂); exact variety cannot be confirmed from the photo

Clear selenite (gypsum)

Gypsum, CaSO₄·2H₂O; selenite is its transparent to translucent crystalline variety

Clear quartz (rough quartz crystal)

Quartz, silicon dioxide (SiO₂)

Orange chalcedony pebble (likely carnelian)

Chalcedony, microcrystalline quartz (SiO₂); orange-red variety commonly called carnelian

Milky quartz

Quartz, silicon dioxide (SiO₂)

Ruby (rough or poorly polished corundum)

Corundum, Al₂O₃; red gem-quality corundum is ruby

Blue sapphire (rough corundum)

Corundum, Al₂O₃; blue color commonly from trace iron and titanium

Pyrite (fool’s gold)

Pyrite, FeS₂; isometric iron sulfide

Likely mica schist

Mica-rich schist, probably muscovite/biotite schist with quartz and feldspar

Small purple crystal fragment, possibly amethyst

Quartz (SiO₂), variety amethyst; identification uncertain from the image

Banded calcite (possibly onyx marble)

Calcite, CaCO₃; banded decorative calcite commonly sold as “onyx”

Iron-rich rock, likely limonite/goethite-rich ore

Goethite (α-FeO(OH)) and/or limonite (a mixture of hydrated iron oxides)

Clear quartz crystal cluster

Quartz (silicon dioxide, SiO₂)

Likely iron-rich breccia or weathered ironstone

Ironstone breccia; composition cannot be confirmed from the photograph

Brecciated jasper with quartz vein

Jasper (microcrystalline quartz, SiO₂) with quartz/chalcedony cement; brecciated silica-rich rock

Banded gneiss

Quartz–feldspar–mica gneiss; exact mineral composition cannot be confirmed from the image

Likely brecciated jasper or iron-stained quartz-rich rock

Jasper-bearing breccia; exact identification requires testing

Iron-rich rock fragment (tentative)

Unidentified iron oxide/hydroxide-rich material; possible hematite or goethite

Possible fossilized tooth or bone fragment

Unidentified fossil; the image is too blurred for a reliable taxonomic identification

Weathered granite fragments

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspars, and mica

Pegmatite fragment

Granitic pegmatite, composed mainly of quartz, feldspar, and mica

Iron-stained quartz or quartzite fragment

Likely quartz (SiO₂), possibly iron-oxide-stained quartzite; exact identification is uncertain from the image

Weathered granite fragment

Granite, a coarse-grained felsic intrusive igneous rock; likely quartz, feldspar, and mica

Iron-stained sandstone

Quartz-rich sandstone with iron-oxide staining (quartz, SiO₂; hematite/goethite, Fe₂O₃/FeO(OH))