I recently received this email from Robert Jason at S. A. Bendheim:
I came across a small German book in our Bendheim archives titled “The Secrets of Glass Painting” dated 1831. As I remember, you were hunting for some ancient color formulations. If you’re interested, please let me know which colors are important for you and if they’re there, we’ll send you a translation.
Here is my reply:
Thank you for remembering my interest. For several years now I have been pursing a research project related to red glass made with copper. My involvement with Bryn Athyn brought to my attention the efforts their craftsmen took to "recreate" a red glass that matched the streaky red glasses of the 12th & 13th century. This glass was eventually made at the Bryn Athyn factory between 1922 and 1942 but the day books and formula are particularly scant. The "secret" of the Bryn Athyn red was apparently closely guarded and went to the grave with the last glassblower.
When I came to this conclusion I turned my focus to the work of Lawrence Saint who was involved with the Bryn Athyn Project from 1917 to 1929. He left Bryn Athyn to work on the Washington National Cathedral. Although Saint was not a glass blower, he was funded by the Cathedral to build a hotshop behind his home in Huntington Valley PA After a period of experimentation his studio began to produce streaky red sheets which are incorporated into his panels in the Washington Cathedral. Saint was very prolific and kept copious notes. Several collections of his materials still exist. I have reviewed these in the archives of the Smithsonian and Corning Museum of Glass.
I am in possession of a copy of Saint's formula but have been unsuccessful in finding a glass blower willing and capable of trying it out. You may remember that I placed several orders with Lambert's and although they were able to come close to the color - they could not match the structure of the glass - which continues to remain completely different from anything available on todays market.
Here is a link to a blog where I have documented my research: http://striatedruby.blogspot.com/I continue to collect information to add to "the pile". I accept your offer and would like to have translations of any recipes concerning red glass made with copper as I am most interested in the "medieval" reds. Any formulas which include gold are a different animal as, from my understanding, gold as a coloring agent didn't show up until the renaissance. Since your volume dates from 1831 I am sure both Saint and the Bryn Athyn Craftsmen were aware of it. Both did extensive research and would have scoured the world for any known formulas. The "lineage" of the Bryn Athyn formulas is interesting in an of itself. Raymond Pitcairn hired a man named John Larson on the recommendation of Tiffany to make glass for him and later to set up the Bryn Athyn Glassworks. Larson's father was a Swedish glassblower who learned his trade at the Kosta factory (think Kostaboda: http://www.kostaboda.com/) I am convinced Bryn Athyn formulas were originally mixed by Larson.
It's all interesting in a very geeky glass way!
On last note: The Summer 2011 I visited the Wissmach factory in West Virginia. They make a glass that is very close to the structure of the medieval reds but since it is table cast it lacks the clarity of mouth-blown sheet glass and fails as a stand in. I continue to remain disappointed that Lambert's can't produce this glass.
Next time I have the opportunity to bend your ear we can talk about how Lambert's should also invest in developing a glass that takes silver stain better.