Mineral Composite

Shark Tooth Fossil

Vertebrate fossilized tooth (various genera such as Carcharodon, Otodus, or Negaprion)

Granite

Phaneritic Plutonic Felsic Rock

Rhodochrosite

Manganese Carbonate (MnCO3)

Dalmatian Stone

Dalmatian Jasper (not a true jasper, typically an igneous perthite)

Lapis Lazuli (polished cabochon/sphere)

Na8[Al6Si6O24]Sn with accessory minerals (Pyrite, Calcite)

Likely rough garnet-bearing rock

Possibly almandine garnet in a metamorphic host; exact identification is uncertain from this photograph

Pyrite with Quartz

Iron Sulfide (FeS2) with Silicon Dioxide (SiO2)

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Sandstone

Arenite (primarily SiO2)

Talc

Mg3Si4O10(OH)2

Biotite

K(Mg,Fe)_3AlSi_3O_10(OH,F)_2

Limonite

FeO(OH)·nH2O

Red Sandstone

Sedimentary Clastic Rock (Quartz Arenite)

Granite

Granite

Gneiss

Gneiss (High-grade metamorphic rock)

Small green-gray pebble (likely serpentinite)

Serpentinite, composed mainly of serpentine-group minerals

Unidentified dark mineral/rock fragment

Indeterminate; appearance may fit a sulfide-bearing rock or iron-rich mineral

Carved serpentine pendant

Serpentine-group minerals, commonly antigorite/lizardite (Mg₃Si₂O₅(OH)₄), possibly mixed with chlorite or other inclusions

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

Orthoclase Feldspar (Potassium Feldspar)

KAlSi3O8 (Potassium Aluminum Silicate)

Limonite

FeO(OH)·nH2O

Limonite

FeO(OH)•nH2O

Limonite / Iron Concretion

Limonite (FeO(OH)·nH2O)

Iron-rich rock fragment (possibly ironstone or limonite/goethite)

Likely ironstone composed largely of goethite/limonite; image alone cannot confirm

Sandstone

Clastic sedimentary rock

Likely weathered granite or granitic gneiss

Quartz–feldspar–mica rock; possibly gneissic granite

Granite

Intrusive Igneous Rock

Quartz Mineral

Silicon Dioxide (SiO2)

Sandstone

Sedimentary rock composed mainly of quartz sand-sized minerals

Weathered granite cobble

Granite, a coarse-grained felsic intrusive igneous rock

Bauxite

Aluminum ore (mixture of gibbsite Al(OH)3, boehmite γ-AlO(OH), and diaspore α-AlO(OH))

Bauxite

Bauxite (Mixture of Al(OH)3, AlO(OH), and Fe2O3)

Blue-green mineral specimen, possibly turquoise

Uncertain from the image; turquoise is hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

Quartz–feldspar pegmatite mineral specimen

Quartz (SiO₂) with potassium feldspar, albite, mica, and likely garnet or tourmaline

Likely olivine (peridot)

Olivine-group silicate, approximately (Mg,Fe)₂SiO₄

Sandstone (with Limonite staining)

Arenite (primarily SiO2 with FeO(OH)·nH2O)

Granite

Granite (composed of Quartz, Feldspar, and Mica)

Magnetite (Lodestone)

Iron(II,III) oxide (Fe3O4)

Biotite-rich gneiss with a dark mafic band

Banded gneiss, likely quartz–feldspar–biotite gneiss (exact minerals uncertain from the image)

Granite

Felsic intrusive igneous rock

Limonite/Goethite on Shale

Hydrous ferric oxides (FeO(OH)·nH2O) often associated with argillaceous rock

Red granite boulder

Granite, a coarse-grained felsic intrusive igneous rock; commonly quartz + feldspar + mica