Scoria
Image: “Jon Zander (<a href="//commons.wikimedia.org/wiki/User:Digon3" title="User:Digon3">Digon3</a>)" (CC BY-SA 3.0)
Mineral NameScoria
Chemical FormulaPrimarily silicate minerals (e.g., plagioclase, pyroxene, olivine) with varying amounts of iron and magnesium
Crystal Systemamorphous
Lusterdull
Streak Colorgray to brownish-black
Cleavagenone
Fractureuneven
Colorsdark gray, black, reddish-brown
Transparencyopaque
Type LocalityWorldwide in volcanic regions
Mineral GroupIgneous Rock (volcanic)
Useslandscaping, construction aggregate, lightweight concrete, gas grill briquettes
Associated Mineralsolivine, pyroxene, plagioclase, volcanic glass
Raritycommon
Description
A dark, highly porous volcanic rock characterized by numerous interconnected vesicles, giving it a sponge-like appearance and low density.
Geological Context
Scoria forms from the rapid cooling of gas-rich mafic to intermediate lava during explosive volcanic eruptions, where trapped gases create its distinctive vesicular texture.
