Fire Clay
Underclay, which consists of siliceous refractory clay rich in hydrous aluminium silicates, is also called fireclay. Just as not all underclays are fireclays, not all fireclays are underclays. Within Carboniferous and other coal bearing strata, fireclay quite commonly comprises many underclays. In Great Britain underclays, which are 1 to 3 metres ( 3 to 9 feet) thick, are major source of commercial fireclay deposits. The alteration of sediments by weathering, plants, and other soil processes comprising underclay resulted in the formation of vast majority of fireclay that comprises underclay.
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Famous quotes containing the words fire and/or clay:
“I’ve seen things you people wouldn’t believe. Attack ships on fire off the shoulder of Orion. I watched seabeams glitter in the dark near the Tennhauser Gate. All those moments will be lost in time like tears in rain. Time to die.”
—David Webb Peoples, U.S. screenwriter, and Ridley Scott. Roy Batty, Blade Runner, final words before dying—as an android he had a built-in life span that expired (1982)
“You may melt your metals and cast them into the most beautiful moulds you can; they will never excite me like the forms which this molten earth flows out into. And not only it, but the institutions upon it are plastic like clay in the hands of the potter.”
—Henry David Thoreau (1817–1862)