as Mart says...its value is in the gold...if you deduct say..a couple of gr, for the stone, then its 22 x $30 ..which is $660...or there abouts.......then the stone..if it is indeed a diamond.....as to its historical value..it only has that value ...if you can link it to someone,..and show it being worn..or were they involved in an heroic act ..other than that, i,d say no....