Loose sandy insulation

What is this stuff?

Old house built approximately 1950. Loose, white sandy/granular stuff throughout most of the attic. Thin - only an inch or two in most areas.

Never seen this before. Can you help me identify it please?

Thanks a bunch and have a great day.

Whoops! Forgot the pics.

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Could be perlite.

That would be my guess as well.
http://www.perlite.net/

Come on Jonathan it’s beach sand from Tahoe. I would agree it’s Perlite and is around a R-3 per inch.