Yogo sapphire
Yogo sapphires are blue sapphires , a colored variety of corundum , found in Montana , primarily in Yogo Gulch ( part of the Little Belt Mountains ) in Judith Basin County , Montana . 
<triplet> Yogo sapphire <subj> corundum <obj> subclass of <triplet> Montana <subj> Judith Basin County, Montana <obj> contains administrative territorial entity <triplet> Little Belt Mountains <subj> Montana <obj> located in the administrative territorial entity <triplet> Judith Basin County, Montana <subj> Montana <obj> located in the administrative territorial entity