This fine specimen is from the premier US locality for ludlamite, the Blackbird Mine of Idaho. The goethite-coated, stalactitic drusy quartz matrix is richly covered with lustrous, olive-green crystals to 8 mm across. They have superb euhedral form, are translucent and sharp. Many more crystals are coated with the goethite. Ludlamite from this locale is world-known as among the best crystals of the species for those characteristics. Ex. John Ydren Collection.