Descloizites from Berg Aukas are generally recognized as the best in the world. While descloizite can be a pretty ugly mineral, the ones from here can actually be really aesthetic in addition to being the best representatives of the species - as this one out of the collection of Ed David is. It has beautifully sharp and well-formed crystals to 1.5 cm, and a fine flashing luster that is uncommon (they can be really dull) .