The advertisement in the newspaper for the auction of the tiara described it a "highly important diamond tiara" which to me indicates that it was considered a valuable item, which the auction price also indicated. As it does not contain any significantly large diamonds, given the price it sold for, I would assume that the diamonds are high quality. I know that many will think this is heresy but there is nothing in the design itself which would warrant a buyer paying a premium to acquire the jewel - it is just that it is an imposing piece; there is nothing discreet about it.