From the Contact page:
I am wondering if there exists a database of the metallurgical compositions of worldwide printing plates from the 15th century to the 20th? Basically, if anyone has pooled together metallurgical data from known plates from museum collections.
I am trying to collect the data to compare it to a 17th-century plate that I have, and such references would be helpful to my research.
If such a compilation does not exist, could you recommend some places that would have a broad collection of copper and bronze plates with metallurgical data to share?