Man Made Material, Not A Natural Rock Or Mineral Specimen

Amazonite

K(AlSi3O8) - Potassium Aluminum Silicate (color due to lead)

Green Jasper

Silicon Dioxide (SiO2) with impurities

Weathered granite (feldspathic, iron-stained granite)

Granite; primarily quartz, potassium feldspar, plagioclase feldspar, and minor mica/amphibole. Exact identification is uncertain from a single photograph.

Bauxite

Bauxite (Al(OH)3, AlO(OH))

Weathered granite or granitic gneiss

Granite; primarily quartz, feldspar, and mica (possibly metamorphosed to gneiss)

Yellow Quartz

SiO2 (Crystalline Silicon Dioxide)

Bull Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Quartz (specifically Milky/Gray Quartz vein)

Silicon Dioxide (SiO2)

Vesicular Basalt or Hag Stone

Basalt (with vesicles) or bored Sedimentary Rock

Polished green aventurine

Quartzite or quartz-rich rock containing fuchsite mica; mainly SiO₂

Iron-rich quartzite or limonite-bearing rock

Quartzite (SiO₂) with iron oxides/hydroxides, chiefly hematite and goethite

Vesicular basalt (probable)

Basalt, mainly plagioclase feldspar and pyroxene, with possible olivine and iron oxides

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

Smoky Quartz in Matrix

Silicon dioxide (SiO2) within Pegmatite/Gneiss

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

Limonite/goethite-rich ferruginous rock; exact identification requires testing

Sandstone

Arenite

Greenstone (Celadonite-bearing Volcanic)

Hydrothermally altered basalt or andesite with Celadonite (K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2)

Unable to identify - Image contains non-geological items

Pink Granite

Phaneritic intrusive igneous rock (Granite)

Quartz Vein in Metamorphic Rock

Silicon Dioxide (SiO2) within Metasedimentary host

Serpentine (Serpentinite)

Serpentinite (complex silicate group including lizardite, chrysotile, and antigorite)

Fire Agate

Silicon Dioxide (SiO2) with Goethite or Limonite inclusions

Yellow Quartz (Citrinated Quartz)

Silicon Dioxide (SiO2)

Weathered iron-rich rock, likely laterite or ironstone

Ferruginous laterite/ironstone, composed mainly of goethite (FeO(OH)), hematite (Fe₂O₃), and clay minerals

Diamond (or Cut Gemstone / Cubic Zirconia)

Carbon (C)

Prasiolite

Silicon Dioxide (SiO2) with iron impurities

River Rock (Basalt or Siltstone)

Basalt (Aphanitic Igneous Rock)

Granite

Felsic Plutonic Igneous Rock

Sandstone (Pebble)

Arenite (primarily SiO2)

Limestone Cobble

Sedimentary Calcium Carbonate (CaCO3)

Ferruginous Sandstone (Ironstone)

Sandstone with Hematite/Goethite cement (SiO2 + FeO(OH))

Gold-bearing quartz vein specimen

Native gold (Au) in quartz (SiO₂), likely with iron-oxide staining

Moldavite

Tektite (Natural Silicate Glass)

Chert / Flint Pebble with Fossil Cavity

Silicon Dioxide (SiO2)

Decomposed Granite

Grano-diorite/Granite-residuum (SiO2 primary)

Iron-rich brown stone, possibly weathered chert or ironstone

Undetermined; likely iron-oxide-bearing silica-rich rock (chert/ironstone)

Yellow Quartz

Silicon Dioxide (SiO2)

Agate

Silicon Dioxide (Chalcedony), SiO2

Marble

Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)

Jasper with Quartz Vein

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

Granite

Phaneritic plutonic rock (composed of quartz, feldspar, and mica)