The degradation of plain-woven fabrics of iron-weighted, lead-weighted, tin-weighted, tin-lead-weighted, and zinc-weighted silks by hydrochloric acid and sodium hydroxide in 10 hours at 40 degrees C has been followed by determining the weight, ash, nitrogen, wet warp breaking strength, and elongation at breaking load of the residual fabrics. These data show weighting is not a factor of the acid or alkaline degradation of silk fibroin and quantitatively compare the degradation of the five weighted silks.