Identification help of ashtray?

Wondering if anyone is familiar with this type of item which looks like a large ashtray? There are large splotches all over, and I cannot tell if it is dried on cigarette ash or part of the decoration? When I washed it, the raised splotches remained. The item is approx 12 inches x 10 inches. I received this item in a box of items that I purchased at an estate sale, so I am unsure of what it is. Thank you for your assistance

 

The shape is typical of both Vallauris and West German mid century ashtrays.

 

Thank you for your information

 

I suppose the English would call it a poxy ashtray.

 

google fat lava.....I had a pair of similar lamps......loved them!!!!

 

Thanks for the tip, I googled that, so interesting! I've never seen those before!

 

Fat lava as a term was coined a fair time after these were made, but it's very apt. Have a really good look at that base. Sometimes, there's a very glazed over mark.