Thank you for submitting your item for appraisal. This appears to be a yellow gold sapphire ring of 2,5 carat and approx. 0,8 carat diamonds. The sapphire is most likely synthetic, the quality of the diamonds is difficult to appraise, this is something a jeweler can do for you hands on. There has been a wide range of results in the recent past, depending on the quality of the stones.
The estimate is based on similar offered or sold at auction.