Industrial mineral site no. 1581, known as "Stemilt Canyon" is a site in Chelan County, Washington. This site has been associated with sandstone. A notation found in DGER Bulletin 37 on page 125 says "High cliffs of soft Swauk sandstone. Washed sample, from which 16 percent clay with fusion of cone 29 had been removed, fused at cone 30 1/2", and designates the value as "Suitable for amber glass and molding or blast sand ".