Pyroclastic rock Reference Libraries
Volcanic ash is the term for very fine rock and mineral particles less than 2 mm in diameter that are ejected from a volcanic vent. Ash is created when solid rock shatters and magma separates into minute particles during explosive volcanic activity. The usually violent nature of an eruption involving steam (phreatic eruption) results in the magma and perhaps solid rock surrounding the vent,...
- A coin originally worth six pennies Scots, and later three; held equivalent to an English halfpenny.
- (in plural) Money; cash.