For all I can see the Chance pista being sold on eBay is a masterpiece-it's well made well and with great skill-the requisites for the common definition of a masterpiece. However, it's merely Chance's masterpiece. Chance seems to have attracted little attention during his time and even less today. In short , it's sort of a miracle by a minor god. As far as value goes, like any collectible, its worth will be decided at the end of the sale.
George Hollenberg MD
CT, USA