WHAT IS PERLITE?

Perlite is formed during volcanic occurrences being the result of the hydration of rhyolitic obsidian, a rock resulting of a sudden chilling (cool down) of molten lava.

This expansion is due to the presence of 2 to 6% combined water in the crude Perlite rock.  When quickly heated to above 1600°F (871°C), the crude rock pops in a manner similar to popcorn, as the combined water vaporizes which accounts for the amazing light weight and other exceptional physical properties of expanded Perlite.

Perlite is a generic term for naturally occurring silicious rock and not a trade name.  The distinguishing feature which sets Perlite aside from the other volcanic glasses is that when heated to a suitable point in it's softening range, it expands from 4 to 20 times its original volume.

CRUDE FORM	Perlite is an amorphous crystal,whichis unique in it's chemical composition where there is almost no presence of crystalline silica. Perlite dates as far back as about fifty million years ago.
CRUSHED FORM	The crude Perlite may range in color from transparent light gray to glossy black. Since Perlite is aformof natural glass, it is classified as chemically inert and has a pH of approximately 7.
EXPANDED FORM	The color of expanded Perlite ranges from snowy white to grayish white. Expanded perlite can be manufactured to weigh as little as 2 pounds/cubic foot, making it adaptable for numerous applications.