[livius]

It’s beautiful and distinctive. I think if you could figure out where the stones came from, that would be a start. Also, knowing the karat would help. European and Latin American gold is normally 18 K, US gold is usually 14K, and then there are the odd ones: 9 karat gold on Malta, for example.

This is a Greek cross (arms the same size) so it could also be from a Byzantine Christian tradition, probably Catholic rather than Orthodox. Lebanese perhaps?

[Bernard Marx]

I think it's a modern piece from one of the air crashes. Actually, the diamond cut style could reveal a lot about its age. There isn't enough detail in the image to help much.

If the diamonds are modern Tolkowsky-style brilliants instead of old European cuts that would definitely date it to the mid-20th century or later. The piece might also have hallmarks that could help with identification.

[tet68]

Nice dark yellow, the design almost looks celtic.
No granulation so it may be modern.
Nice find, I’d go back .

[tet68]

How the stones are cut would probably tell a lot,
the cross looks like amethyst.