They mostly end up in trusting what a salesperson shows or tells them about a diamond ring. In such cases, the chances to get ripped off or scammed are much higher, and since it is important to avoid that, you need proper knowledge about the quality of diamonds and settings.   The main thing that you must learn about diamonds is its 4C; cut, color, clarity, and carat weight. These are what mainly determine the quality of a diamond. Out of these, the cut quality is the most important, as it is associated with the shine of the gemstone. Additionally, certification done by a third party is equally important. For instance, consider a GIA certificate, which documents all the details about a diamond. It would not have details about the metal quality, diamond settings, age, etc, so, you would need to take the ring to an independent appraiser to find out those things.