Mineral (Man Modified)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Polished bumblebee jasper (likely)

Calcite–sulfur-rich volcanic breccia, commonly sold as “bumblebee jasper”

Likely pale green-yellow fluorite

Fluorite (calcium fluoride, CaF₂)

Green fluorite (likely)

Fluorite, CaF₂

Red jasper (likely iron-rich chert)

Microcrystalline quartz (SiO₂), colored mainly by hematite/goethite impurities

Banded agate/chalcedony fragment

Microcrystalline quartz (SiO₂), likely banded chalcedony or agate

Celestite

Celestine (SrSO4)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Greenstone, likely serpentinite

Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), possibly with magnetite and chlorite

Serpentine-rich rock, possibly chrysotile serpentine

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite, brucite, or talc

Milky quartz (rough quartz fragment)

Quartz, SiO₂

Fluorite

Calcium fluoride (CaF2)

Polished septarian nodule cabochon

Septarian calcite–aragonite nodule, commonly in a clay-rich limestone/marl matrix

Likely slate fragment

Slate; fine-grained foliated metamorphic rock composed mainly of clay minerals, quartz, and mica

Pink-purple rough mineral specimen (possibly lepidolite-bearing mica)

Lepidolite, a lithium-rich mica; identification is uncertain from the photo

Granite

Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase)

Native Copper

Native Copper (Cu)

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Iron-rich concretion or weathered ironstone

Goethite–hematite-bearing ironstone; identification is uncertain from appearance alone

Diorite

Diorite (intermediate plutonic rock)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Pegmatitic granite specimen

Granitic pegmatite, chiefly quartz (SiO₂), feldspar, and mica

Likely hornblende amphibolite fragment

Amphibolite, chiefly hornblende and plagioclase feldspar

Serpentinized ultramafic rock (likely serpentinite)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite, olivine, pyroxene, and sulfides

Possible iron-oxide concretion with a dark mineral cap

Iron-oxide–cemented sedimentary concretion; exact composition cannot be determined from the image

Quartz-bearing weathered rock

Massive to drusy quartz (SiO₂), possibly in a feldspathic or carbonate host

Quartz-rich rock fragment

Likely milky quartz (SiO₂), possibly a pale quartzite fragment

Tumbled quartz (likely smoky or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Likely rough quartz-bearing mineral specimen

Quartz (silicon dioxide, SiO₂), possibly iron-stained quartz or quartz-rich rock

Weathered fossiliferous limestone fragment, possibly fossil coral or shell material

Indeterminate carbonate fossil in calcitic limestone; likely composed mainly of calcite (CaCO₃), but species identification is not possible from this image alone

Citrine or Yellow Quartz

Silicon Dioxide (SiO2) with iron impurities

Serpentine-rich serpentinite

Serpentinite, chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), with possible magnetite, brucite, and carbonate

Tumbled quartz-rich pebble, possibly milky quartz or quartzite

Quartz (SiO₂), potentially quartzite if metamorphically recrystallized

Tumbled white quartz

Quartz (silicon dioxide, SiO₂), likely milky quartz

Polished chrysocolla cabochon

Chrysocolla, a hydrated copper phyllosilicate; commonly intergrown with quartz, malachite, or other copper minerals

Gold Nugget

Native Gold (Au)

Polished chrysocolla (possibly chrysocolla-in-quartz)

Chrysocolla, a hydrated copper silicate; commonly approximated as Cu₂H₂Si₂O₅(OH)₄·nH₂O

Mixed tumbled stones

Mixed aggregate of quartz, chalcedony, jasper, feldspar, and other common silicate minerals

Serpentinite (likely veined variety)

Serpentinite; chiefly serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and carbonate veins

Milky quartz with iron-oxide staining

Quartz, silicon dioxide (SiO₂), with hydrated iron oxides

Quartz geode

Quartz, SiO₂; likely a chalcedony-lined geode with inward-growing quartz crystals