from The Century Dictionary.
- noun See
Sorry, no etymologies found.
About 100 yards higher up the stream black vesicular trap is seen, penetrating in thin veins the clay shale of the country, converting it into porcellanite, and partially crystallizing the coal with which it came into contact.
Other important finds include a stone ax, which came from England's Lake District, and other axes made from the rock porcellanite, which only occurs in the North Antrim area.
Some types of pozzolanic materials are: pulverized fuel ash, blastfurnace slag, volcanic ash, diatomatious earth, under-fired clay bricks, porcellanite and others.