More Information on:

Fine Line: Drawing With Silver in America [Paperback] by Bruce Weber.

The Luminous Trace: Drawing and Writing in Metalpoint [Hardcover] by Thea Burns. Available for preorder on Amazon.

"Silverpoint Drawing Series, 1967 - 1981" by Howard Hack. Published by the Fine Arts Museums of San Francisco, 1981. Limited availablity. Sometimes is available on Amazon.

Silver Linings by Banjie Getsinger Nicholas. An introduction to silverpoint. Published February 2012.