For Diamonds that are visually eye clean and bright to the naked eye, the most affordable option is the color range G-H, with a clarity of SI1 with cut and polish as a factor. Since most inclusions in SI1 are not easily seen unless using a 10x jewelers loupe, I'm careful to not choose Diamonds with inclusions center on the table and find those with minimal inclusions toward the angling of the crown.
The process of choosing the perfect Diamond can be a lengthy one, and picking the best one within your budget is my highest priority. With that said, I only choose Diamonds that I would personally pick for myself within your budget range that I'm working with. I offer SI1 as a base standard for my line but a higher clarity and color Diamond can be purchased.
Canadian sourced Canadamark GIA Diamonds are also available.