The amorphous structure and the very high silicon dioxide content are two of
the keys to the performance of silica fume a pozzolan. There is no
particular threshold for silicon dioxide content. Most of the silica fume
used to date has been above 85 percent, and this value has been maintained
in most specifications.
The Silica Fume Association
38860 Sierra Lane, Lovettsville, VA 20180
Tel: 540.257.4224 Fax: 540.822.9456