Purchased a couple of stone they appear to be Kyanite. They we’re completely misidentified by the seller. The pricing guide doesn’t have Kyanite listed. The test inidicate it has an RI of ~1.71 and SG of 3.57. Here are some pictures.
Weight is 18.175 cts. The color is light but matches some forms of Kyanite as does the specs, and the Clarity is near flawless for such a large stone. I will be doing a conductivity test later this week. Values are not listed on the guide.