Sedimentary (Secondary Classification For A Weathered Mineral Specimen)

Polished orbicular granite (likely larvikite-type stone)

Coarse-grained granitoid composed mainly of feldspar, quartz, and dark mafic minerals; exact variety is uncertain from the image

Limonite (Yellow Ochre)

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

Basalt with Secondary Mineralization (Likely Zeolites or Calcite)

Aphanitic mafic volcanic rock with secondary mineral inclusions (e.g., CaAl2Si3O10·3H2O for Scolecite)

Limonite (Ironstone Concretion)

Limonite (FeO(OH)·nH2O)

Limonite

FeO(OH)·nH2O (Hydrated iron oxide)

Agate

Silicon Dioxide (SiO2)

Feldspar-rich igneous rock, likely granite or gneiss fragment

Granite-like quartz–feldspar rock; exact identification is uncertain from the blurred image

Agate Pebble (Desert Agate / Chalcedony Nodule)

Silicon Dioxide (SiO2)

Limonite with Trace Fossils

Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)

Turquoise

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

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Limonitic Iron Ore / Goethite

Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)

Limonite (with Pyrite)

Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O

Vesicular basalt (possible scoria)

Basaltic volcanic rock; chiefly plagioclase, pyroxene, and iron-rich minerals, with vesicles formed by trapped gas

Vesicular basalt (scoriaceous volcanic rock)

Basalt, chiefly plagioclase, pyroxene, and commonly olivine; vesicles may be lined with secondary minerals

Vesicular basalt (likely weathered lava rock)

Basalt; chiefly plagioclase, pyroxene, and often olivine

Weathered pink granite cobble

Granite, likely biotite-bearing pink granite; exact variety cannot be confirmed from a photograph

Sandstone with Quartz Veining

Arenite with SiO2 veins

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Weathered rounded pebble

Likely altered granite or granitic gneiss fragment; exact identification is uncertain from the image

Ferruginous Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Chert (specifically Agate/Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Limonite (Iron Ore)

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

Limonite (Iron Ore)

Limonite (Hydrous iron(III) oxide-hydroxide mixture, FeO(OH)·nH2O)

Chert (Jasper/Flint variety)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Yellow Quartz

SiO2 (Crystalline Silicon Dioxide)

Chondrite Meteorite

L or H Ordinary Chondrite

Limonite

FeO(OH)•nH2O

Limonite

Limonite (Hydrous iron oxides, predominantly Goethite FeO(OH)·nH2O)

Weathered iron-rich rock, possibly laterite or limonite-bearing stone

Hydrated iron oxides/hydroxides, chiefly limonite-goethite mixture; exact identification requires testing

Iron Ore (Limonite and Hematite)

Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)

Calcite with iron staining

Calcium Carbonate (CaCO3)

Iron-stained Quartz / Chalcedony Pebble

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Turquoise

Turquoise - CuAl6(PO4)4(OH)8·4H2O

Chert (Flint) with Limonite Staining

Microcrystalline Quartz (SiO2)

Limonite and Goethite encrusted Chert/Ironstone

Hydrated Iron Oxide (FeO(OH)·nH2O) with cryptocrystalline Silica (SiO2)

Limonite / Goethite Ironstone

FeO(OH)·nH2O (Hydrous iron oxide)

Malachite

Copper carbonate hydroxide [Cu2CO3(OH)2]

Yellow Ochre / Limonite

Limonite (inter-mixed iron oxides and hydroxides, primarily FeO(OH)·nH2O)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Quartz (Sea Glass or River-worn Pebble style)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)