Antropogenic (Man Made)

Fine-grained dark igneous rock, likely basalt

Basalt; predominantly plagioclase feldspar and pyroxene, commonly with minor olivine and iron-titanium oxides

Red Jasper

Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions

Limestone

Sedimentary Calcium Carbonate (CaCO3)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite

Limestone

Calcium Carbonate (CaCO3)

Sandstone (likely Graywacke or Arkosic varieties)

Arenite (composed primarily of SiO2)

Likely basalt or dark volcanic rock

Basalt; predominantly calcium-rich plagioclase and pyroxene, possibly with olivine

Dark basalt or fine-grained mafic rock

Basalt; primarily plagioclase feldspar, pyroxene, and commonly olivine or iron-titanium oxides

Sandstone (Quartzite-rich)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Granite Pebble

Granite

Limestone

Calcium Carbonate (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Granite Pebble

Granite (composed primarily of Quartz, Feldspar, and Mica)

Limestone Pebble

Sedimentary Calcium Carbonate (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Clear Quartz

Silicon Dioxide (SiO2)

Sandstone

Arenite (SiO2 dominant)

Banded Iron Formation

Banded Iron Formation (BIF)

Turquoise

Turquoise (Hydrated copper aluminum phosphate, CuAl6(PO4)4(OH)8·4H2O)

Dark igneous rock, likely basalt

Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with olivine

Black basalt (likely polished or cut fragment)

Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase, clinopyroxene, and often olivine or magnetite

Tumbled pink granite or feldspar-rich granitic pebble

Granite, composed mainly of quartz, potassium feldspar, and plagioclase; exact identification is uncertain from the image

Limestone

Calcium Carbonate (CaCO3)

Granite

Phaneritic plutonic rock (Quartz, Feldspar, Mica)

Limestone (with potential fossil inclusions)

Calcium Carbonate (CaCO3)

Granite

Phaneritic Plutonic Felsic Rock (SiO2 > 69%)

Limestone (Grey and White specimens)

Calcium Carbonate (CaCO3)

Blue-green mineral specimen, likely chrysocolla or turquoise

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

Polished agate/chalcedony fragment

Microcrystalline quartz (SiO₂), likely banded chalcedony or agate

River Stone (Limestone)

Sedimentary Calcium Carbonate (CaCO3)

Milky Quartz

Silicon Dioxide (SiO2)

Granite

Granite (Phaneritic igneous rock)

Granite

Granite (Felsic Plutonic Rock)

Limestone

Calcium Carbonate (CaCO3)

Granite

Granite (Felsic Plutonic Rock)

Granite

Phaneritic Igneous Rock (Granite)

Granite

Granite (Felsic Plutonic Rock)

Quartz

Quartz (SiO₂)

Granite

Granite (dominated by Quartz, Alkali Feldspar, and Plagioclase)

Limestone

Calcium Carbonate (CaCO3)