Wendy & Frank Melanson Collection American collectors are not often generally familiar with Rudabánya as a source of fine copper minerals, but after a visit to the Narodny Museum in Prague some years ago I became a believer. Specimens on display there rivalled the best azurites and malachites from anywhere. This TN copper is not world-class, but the sharp lustrous crystal is a very nice example of a spinel-law twin.