Silver Counterfeit Of A 2.50 Gold Coin

Has anyone seen anything like this? The diameter is exactly correct (18 mm) but the weight is not surprisingly low -- 2.72 g. It is exactly 1 mm thick. It's been scraped pretty heavily and does have a bit of pale yellow to it suggesting it may have been plated at one point.

The design is not quite right for a 2.50. It tests as a 90% silver pre-1900 coin, which makes me wonder if a foreign silver coin was coined into this.