Yes 800, and 900 was a standard in many of the European Countries, Known as Coin Silver. This is a very common Purity, seen commonly in Flatware and Holloware of the time. This was commonly used as money, you could take your Flatware and have it turned into Coin and Vise Versa. Hence the name Coin Silver. Today we call 800 Silver Alloy, 900 is considered as Coin and Sterling being 925, and Fine Silver being 999.