This is an example of vermiculite in an attic.  Vermiculite is a naturally occurring rock, much of which contains asbestos.  The most common form is short cylinders, that fracture into small pieces easily, with a grey metallic color.  Vermiculite was used to insulate attics and walls in the early part of this century, until someone figured out that asbestos is bad for you.  Asbestos causes mesothelioma, which is a disease that attacks the outer layer of the lungs, with a very poor prognosis.  If your attic has vermiculite, my recommendation would be to have it tested for asbestos.  If the test is positive, you can have the vermiculite abated by a company certified by the Washington State Department of Labor and Industries

This is what an attic full of vermiculite looks like.  Don’t disturb this product for any reason unless you have been trained and have the proper gear.