HELP IDENTIFY AN INTERESTING RING !!!

[Roman]

HELLO TO ALL GOOD PEOPLE :) !!!
HELP IDENTIFY THE BRAND ON THE RING?
WHOSE COUNTRY?
WHAT FOR METAL?
(Weight 8.95 g., Diamond cr. 57, 0.28 3/5)
PHOTO BRANDS UNDER MICROSCOPE




(admin edit - see Posting Requirements )

[AG2012]

Hi,
Warsaw,Poland,mark for 18 Carat gold (.750) used since 2012.
No appraisals here.
Regards

[Roman]

THANK YOU!!! YOU ARE THE BEST!!!!