It's stamped on a back "750" "1949"
Sapphires and diamonds are natural.
I would really appreciate any your thoughts about it.
I could get more images if it is necessary.
Unfortunately, that's not much information to go on. The "750" most likely indicates that the piece is made of 18k gold - but you probably already know that. A quick search of the didn't turn up any "1949" jewelry marks, but you might give trademarkia a try: