Always purchase quality over size. You will wish you did some time afterward. My saying is "I would rather sell you a fine quarter carat, instead of an inferior half carat! I have sold diamonds for over 50 years. You can clean a fine diamond and its brilliance returns, but you can use the strongest Ultrasonic Machine in the world and never bring that type of brilliance to an inferior low quality diamond.

Choose a good Color of diamond such as a G to H Color; try to choose a Clarity of SI1 at least. Needless to say choosing better than this will only make both parties involved happier in the years to come. Always remember that in this case for sure, size is not the issue.

Choose a reputable Jeweler. There is usually at least one surviving in each town. I am not trying to say that the larger chain stores are not a good store to purchase from. It is only my opinion, since I grew up working in an independent family own jewelry store and know how we buy and sell.