Sedimentary (Secondary Classification For A Weathered Mineral Specimen)

Limonite (Iron Ore)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Lunar Meteorite (Feldspathic Breccia)

Lunar Feldspathic Breccia

Limonite and Goethite

Limonite (hydrated iron(III) oxide-hydroxide) and Goethite (α-FeO(OH))

Iron Meteorite

Siderite (Iron-Nickel Alloy)

Porphyritic basalt

Vesicular/porphyritic basalt, chiefly plagioclase and pyroxene with iron-oxide alteration

Pyrite-rich Ore

Pyrite (FeS2) with secondary minerals

Granite countertop slab

Granite; primarily quartz, feldspar, and mica (commonly biotite), with accessory amphibole/iron oxides

Iron-stained chert or weathered ironstone nodule

Microcrystalline quartz (SiO₂), possibly limonite/goethite-bearing

Milky Quartz Pebble with Inclusions

Quartz (SiO2) with chlorite or mica inclusions

Limonite (Iron Ore)

FeO(OH)·nH2O

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Turquoise

Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O

Weathered vesicular basalt (likely amygdaloidal basalt)

Basalt, composed mainly of plagioclase feldspar, pyroxene, and altered olivine; cavities may contain secondary zeolite, calcite, or silica

Ferruginous Siltstone or Mudstone

Ferruginous Siltstone / Goethitic Sandstone

Chert (with Quartz Veining)

Microcrystalline Quartz (SiO2)

Green Tourmaline

Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4)

Polished yellow-brown jasper

Jasper, a microcrystalline variety of quartz (SiO₂), commonly containing iron-oxide impurities

Sandstone (Limonitic/Iron-stained)

Sandstone (containing Quartz, SiO2, and Limonite, FeO(OH)·nH2O)

Yellow Ochre / Limonite

Limonite (FeO(OH)·nH2O)

Vesicular volcanic rock, likely scoria

Scoria; typically basaltic to andesitic composition, chiefly plagioclase, pyroxene, and volcanic glass

Limonite (Ironstone)

Limonite (FeO(OH)·nH2O)

Limonite (Gozzany Iron)

Limonite (FeO(OH)·nH2O)

Iron meteorite (probable)

Fe–Ni metal, commonly kamacite and taenite

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Limonite on Sandstone

Iron Oxyhydroxide (FeO(OH)·nH2O) on Quartz Sandstone

Pitted vesicular basalt, likely copper-stained

Basalt (mafic volcanic rock), possibly with secondary copper minerals such as chrysocolla or malachite

Quartz (Iron-stained)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Turquoise (likely stabilized or simulated Howlite)

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)

Turquoise

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

Limonite (Iron Stone/Goethite)

Limonite (mixture of hydrated iron oxides, primarily Goethite: α-FeO(OH))

Granite Cobble

Phaneritic plutonic rock (dominated by Quartz, Feldspar, and Mica)

Limonite with Gossan / Iron Ore

Hydrated iron oxide-hydroxide, approximately FeO(OH)·nH2O

Limonite (Iron Ore)

Limonite (mixture of hydrated iron(III) oxide-hydroxides)

Hematite

Iron(III) oxide (Fe2O3)

Quartz-rich granite or granitic pegmatite

Granite; chiefly quartz (SiO₂), potassium feldspar and plagioclase, with minor mica/iron oxides

Kaolinite (Chalky Clay)

Kaolinite (Al2Si2O5(OH)4)

Limonite (Ironstone)

FeO(OH)qn H2O

Copper-bearing rock, likely chrysocolla–malachite with limonite

Chrysocolla (hydrated copper aluminosilicate) and malachite (Cu₂CO₃(OH)₂), with iron oxides and possible native copper

Iron-rich meteorite candidate

Provisional: stony-iron or iron meteorite; exact classification requires testing

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Rhodochrosite with Quartz

Manganese Carbonate (MnCO3) with Silicon Dioxide (SiO2)

Quartz-encrusted Matrix

Silicon Dioxide (SiO2) with Ferruginous Sandstone