The market is trading this elegant gem stone under the name “Crown Psilomelane Agate”. The name refers up that unusual black, partly metallically reflecting appearance of this agate and to its content of a manganous oxide, which is rather inconspicuous at other place. To the unusual aesthetic effect of this material owed is probably the alternative name “Merlinite” (after the legend Merlin was the mentor and wizard of king Arthur).
The black metallically shining psilomelane is in-grown in a banded chalcedony. Together they are actually representing an agatized ore-vein. In this vein cavities are showing up, which are decorated with small, intensively glittering quartz crystals. These areas are representing also the actual “piéce de resistance” of the material: North American jewellry-designers are wining black-based cabochons of the “druzy-quality” out of it .Their sparkling fascinates the female customers enthusiastically. Cabochons, which are cut from not crystallized ranges, possess a rather calm strong radiant emittance
A more exact location than “Chihuahua” for this material is unfortunately not known to me for the moment.