The Rosenthal part is more or less irrelevant here, but still: the original item was made by the [i]Rosenthal AG[/i] at their factory in Kronach, Bavaria, between 1933 and 1955. Series (body) name “VIKTORIA”. The item was then re-decorated by the [i]Metallporzellan Deusch[/i] from the town of Lorch in Baden-Wuerttemberg.
The silver overlay consists of coin grade silver and requires certain treatment as to not cause excessive tarnishing or damage. There are collectors out there which collect such goods either in general or by creator (Deusch, Veyhl, etc.). I have noticed that eBay closed auction prices in this sector are often far away from floor prices at meets or auctions, so one can not really use eBay as price range indicator.
[b]@marthahill:[/b] Some companies marked with country of origin regardless if an item was intended for import or not. Another exception would be goods in post-war Germany which were sold to the Allies via the NAAFI (UK) or PX (US) stores.