A diamond price for a ring can vary according to the diamond or diamonds used and the precious metal used for the ring.
The value or price of a diamond will depend on the quality of the diamond, its characteristics and its size.
The quality and characteristics are most important. What sort of cut is the diamond? What is its color, its clarity? The better quality diamond for the size the more expensive it is.
Probably your budget will be the first determining factor as to what sort of diamond you can buy. Diamonds can range from a few hundred dollars to many hundred of thousands. The price of a diamond will also increase expotentially to its size. Whereas a good quality diamond might fetch 2000 to 5000 per carat in the one to two carat sized, When you get to the 10 and 20 carat sizes the price per carat can jump to 10,000 to 30,000 dollars per carat. This is because the larger the diamond the more rare it is. 95 percent of all diamonds are industrial grade only and worth just a few dollars. They are used in industry for grinding and polishing among other uses.
Whatever your budget try to buy a diamond at the top of your range. That way you get the best possible diamond you can afford.
Ensure that the diamond comes with a proper certificate from an independent gemological laboratory, even if it is set in a ring.
Inspect the diamond and ensure that the setting in the ring is tight and it is not a loose diamond in anyway.
You should get a written statement also that the ring is what it is supposed to be. Gold, what type or Platinum and what karat it is.
Doing some patient browsing for a diamond price ring will ensure that you get the right diamond price before you buy.