Millet-Seed Sandstone
Image: “Jon Zander (<a href="//commons.wikimedia.org/wiki/User:Digon3" title="User:Digon3">Digon3</a>)" (CC BY-SA 3.0)
Mineral NameMillet-Seed Sandstone
Chemical FormulaSiO2 (predominantly)
Mohs Hardness6
Streak ColorWhite
CleavageNone (for the rock; quartz has no cleavage)
FractureGranular to uneven
Specific Gravity2.2
Colorsreddish-brown, tan, light brown
TransparencyOpaque
Type LocalityNot specified
Mineral GroupSedimentary Rock (clastic)
Usesbuilding material, construction aggregate, reservoir rock for oil and gas
Associated Mineralsquartz, feldspar, mica, clay minerals, iron oxides (cement)
Raritycommon
Description
A reddish-brown, granular sedimentary rock, approximately 4 cm in size, characterized by visible, well-rounded sand grains, giving it a somewhat rough texture.
Geological Context
Millet-seed sandstone forms in sedimentary environments, typically eolian (wind-blown deserts), where sand grains are well-rounded and sorted before being cemented together. It indicates ancient desert conditions.
