Re: DE/Silica
http://en.wikipedia.org/wiki/Diatomaceous_earth
Diatomaceous earth (pronounced /ˌdaɪ.ətɵˌmeɪʃəs ˈɜrθ/) — also known as DE, TSS, diatomite, diahydro, kieselguhr, kieselgur, brand names include Celatom or celite — is a naturally occurring, soft, chalk-like sedimentary rock that is easily crumbled into a fine white to off-white powder, with a particle size extending from less than 1 to over 100 microns, but typically around 2 to 10 microns. [1] This powder has an abrasive feel, similar to pumice powder, and is very light, due to its high porosity. The typical chemical composition of diatomaceous earth is 86% silica, 5% sodium, 3% magnesium and 2% iron.
Why do you believe it has alumium in it? I have never heard that.