In white colorless diamonds the obvious answer for most expensive is D (the diamond color chart goes from D-Z). But in colored diamonds... While there can be debates about which is more expensive, the blue diamond or the pink diamond however Red Diamonds are the rarest and thus the most expensive diamond color!.
http://www.naturallycolored.com/blog/are-colored-diamonds-more-expensive/
FYI My wife's Leo wedding diamonds are valued at $20k and insured.
COL Mikel J. Burroughs
Are Colored Diamonds more Expensive? - Naturally Colored
Are Colored Diamonds more expensive? Are Yellow Diamonds more expensive? What should I Buy? If you are looking for an answer we invite you to read this post.
http://www.levian.com/brandedbylevian/chocolate-by-petite-le-vian/#YQEN 45
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