Sedimentary (Secondary Classification For A Weathered Mineral Specimen)

Greenschist (Greenstone)

Chlorite schist (primarily Chlorite-Epidote-Actinolite-Albite)

Vesicular Basalt

Extrusive Mafic Igneous Rock with Vesicular Texture

Limestone (Ocherous)

Calcium Carbonate (CaCO3) with Iron Oxide (Limonite)

Porphyritic granite boulder

Granite, commonly quartz–alkali feldspar–plagioclase with biotite/hornblende

Weathered basaltic river pebble

Basalt, likely with iron-oxide weathering and secondary alteration minerals

Erythrite (or Lab-Grown Cobaltite/Cinnabar Analog)

Erythrite (Co3(AsO4)2·8H2O)

Unidentified small brown rock

Undetermined; image does not show enough detail for reliable identification

Vesicular basalt with secondary mineralization

Mafic volcanic rock, chiefly plagioclase and pyroxene, with iron oxides and likely zeolite/calcite infillings

Agate (or Chalcedony pebble)

Silicon Dioxide (SiO2)

Quartz pebble

Silicon dioxide (SiO2)

Limonite

Limonite (FeO(OH)·nH2O)

Small weathered mineral/rock fragment

Uncertain from image; possibly quartz-rich sandstone or a feldspar-bearing rock

Possible iron-rich meteorite fragment

Undetermined; possible stony-iron or iron-oxide-rich meteorite

Weathered Sandstone Cobble

Arenite / Quartz Sandstone

Vesicular basalt with pink mineral inclusions

Basalt, likely porphyritic/vesicular basalt; inclusions may be calcite, zeolite, or weathered feldspar

Iron-stained Quartz Pebble

Silicon Dioxide (SiO2) with Hematite/Limonite coatings

Chrysocolla in Quartz

Hydrated copper phyllosilicate with silicon dioxide (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O + SiO2)

Mica-rich Sandstone or Micaceous Schist Weathering

Micaceous Schist (Muscovite-Quartz composition)

Vesicular basalt (likely weathered scoriaceous basalt)

Basalt, primarily plagioclase feldspar, pyroxene, and iron-rich oxides; approximate composition 45–52% SiO₂

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Polished volcanic scoria or vesicular basalt

Vesicular basalt; primarily plagioclase, pyroxene, and iron-rich glass/oxides

Copper Ore (Malachite and Azurite on Host Rock)

Cuprite, Malachite, and Azurite dissemination in gangue

Yellow Jasper / Chalcedony

Silicon Dioxide (SiO2) with iron inclusions

Sandstone (River Cobble / Pebble)

Sedimentary Rock (Quartz Sandstone / Arenite)

Limonite / Goethite Ironstone Concretion

FeO(OH)·nH2O (Hydrated Iron Oxide)

Iron-rich concretion or weathered limonite/goethite nodule

Limonite (hydrous iron oxides), commonly dominated by goethite (FeO(OH))

Foliated metamorphic rock, likely gneiss or mica schist

Quartz–feldspar–mica metamorphic rock; exact identification is uncertain from the photograph

Optical Calcite

Calcite (Calcium Carbonate, CaCO3)

Sandstone (lithic)

Lithic Wacke / Arenite

Ammonite Fossil

Ammonoidea

Agate

Chalcendony (Silicon Dioxide, SiO2)

Native Copper

Native Copper (Cu)

Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Quartz (Milky/Common Quartz)

Silicon Dioxide (SiO2)

Quartz (Microcrystalline/Gravel)

Silicon Dioxide (SiO2)

Weathered dark volcanic rock, likely basalt

Basalt; predominantly plagioclase feldspar and pyroxene, with possible olivine and secondary alteration minerals

Weathered foliated metamorphic rock, likely schist or gneiss

Mica schist to gneiss; commonly quartz + feldspar + biotite/muscovite

Turquoise

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

Limonite (Iron Ore)

Limonite (Hydrated iron oxide - FeO(OH)·nH2O)

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Yellow Ocher / Limonite

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)