Randy— I believe you’re referring to the Hahnemuhle platinum paper that was just introduced. It’s not actually platinum printing paper. It’s just an ordinary (and really well-made) paper that is compatible with the platinum process. But even if it was a pre-sensitized platinum printing paper, I wouldn’t include it in a 19th century Photographic Prints ID Chart. Nearly every historic photographic process from daguerreotypes to Lippmann plates to Bromoil has modern day practitioners. However, these contemporary artists are 1) not making prints in the 19th century and 2) they’re relatively marginal in terms of significant commercial usage today. I’m not belittling the artists who make use of 19th century processes today, but it’s useful for collections care professionals to understand when a process was commercially significant and therefore when the historic prints in their collections were likely made.

best,

Gawain