This mineral is found in crystals only in California, where it represents a rare form within the hexagonal system, the ditrigonal-dipyramidal crystal shape. This sharp dark blue crystal, perched on matrix, is well formed, slightly transparent, and has good luster. The crystal measures 1.6 cm across. One termination has been repaired, but does not affect the visual quality of the specimen although it lowers the price from $2000 or so in my opinion. Still, displays like a killer and you have to look close to notice the repair.