A “buy shy” diamond is one that’s weight is just shy of a major carat threshold such as 1.90ct instead of a 2ct. Just like mined diamonds, lab diamonds are priced mostly by their carat weight, with the price per carat at 1, 1.5, 2, 2.5, and 3 carats at much higher rates than just below those thresholds. Buy shy diamonds are similar in carat weight and may be indistinguishable to the naked eye from a much more expensive alternative. Buy shy diamonds are also very popular and sell fast!