How much is a s1 d 1 carat diamond worth?

Your diamond is worth whatever someone will pay you for it.

You can buy such a diamond today on Blue Nile and spend between US$3,297 and US$3,866, depending on the cut you want.

Best practices dictate that you pay for a certified gemologist to evaluate your diamond and verify its grades. This will give you a better way to establish a fair market value.