The official state stone of California , benitoite is a rare blue-purple stone that is seldom seen in the market. Collected by connoisseurs, this isn't a hardy stone, rating only 6.5 on the Moh scale, but it more than makes up for it in color. Found in small pieces of point weight, full carat weight benitoite are atypical and a fine-grade 1 carat stone can cost up to $3000 and a 2 carat weight will cost substantially more than $7000. The usual price for half carat to 1-carat weight is about $750 to $1500 for good grade stone. The most common colors found are blue with violet tints and undertones. Less common are the true purple-violet kind and even rarer are the pink variety. Displaying an amazing amount of brilliance, these stones are every so often mistakenly identified as blue diamonds, showing a fine dispersion of rainbow colors and great sparkle.