Advice please; found an old ring

Hello everyone,
I need some advice please and am hoping Ive found the right place! My husband found a ring under a house he is renovating and we are struggling to identify it. It is silver, very chunky with a large amethyst (1cm) in it and what look like tiny diamonds (92 in all)clustered all around it. There is also a third stone which we can’t identify, forming a cross shape around the amethyst.
It’s a very heavy ring, and looks like a mans. It also has the appearance of being Eastern. The only hallmarks on it, which have been slightly worn, are the numbers 925, 16 and what appears to be 81. There are no other hallmarks that we can see. If anyone has any idea where this ring may have originated from? or if there are any recommended websites which may be able to help me? Id really appreciate it as it’s a very unusual and detailed ring which we’d love to identify!
Thank you in advance for any help or advice. :smiley: