Beautiful Silver and Crystal Floral Center Bowl

So it looks like pewter but tested as strong as any sterling pieces I have tested. Before I polished it, it was black. Very heavy and the floral work is intricate. The crystal bowl is removable but does fit as if it was made for it. There is only one small stamp which is '90'. I believe the Germans used the 90 mark for silverplate that was 90% fineness? Any help would be appreciated.

 

I think it was also used on Dutch silver plate too. Lovely bowl.

 

The attached article explains the use of numbers on European silver plate. The number stands for the quantity of silver (measured in grams) used in the plating, not the fineness of the silver itself.

https://www.925-1000.com/a_platenumbers.html

 

Thanks I had already seen this article as well. I guess what is confusing is why this piece is testing as sterling and testing really strong?

 

The plating is done with high fineness silver and in this case at 90 grams, is very thick. So it does not surprise me that normal "home methods" for testing are yielding that result.

What testing method did you use?

 

I used the testing kit with scratch stone for gold silver and platinum.

 

The thing is that a scratch stone may not be scratching deeply enough into the plating layer to get down to base metal. It's testing the plating only - This happens all the time.