This is a very old classic Tsumeb mineral from the 1st oxidation zone, circa early 1900s or even the late 1800s. The rare mineral Bayldonite has replaced mimetite crystals and so now, spraying out from a matrix of massive bayldonite, is a cluster of bright, apple green, crystals of the same mineral that have retained the mimetite crystal form. The sprays of crystals reach .5 cm in length. The color and rarity overcomes the damage to some crystals (visible in the photos), so this is still quite displayable! 4.1 x 3.8 x 3.6 cm