This is a rare double replacement of minerals the likes of which is only found at Tsumeb, and this is a very large example with incredibly robust crystals of these copper species! There are two pairs of "Azurite" crystals on this attractive and unique piece, each in parallel orientation that show this pseudomorphism (replacement) very well. The prominent crystal is rather fat and large at 6 cm in length and the adjacent one measures 3 cm. They have at least two other smaller crystals in parallel growth with each of them making for an interesting cluster. These crystals first grew as Azurite crystals which were later altered to Malachite, and then replaced again as the pocket chemistry changed, into this magnificent, turquoise blue-green Rosasite. There are other crystals on the backside of the piece that measure 2.8 and 1.3 cm in size and show the same pseudomorphism. The specimen is accented with bright white, intergrown, concave patches of Calcite and a rosette of white Calcite on the back that is 1.5 cm across. The blue-green Rosasite and stark white Calcite provide great contrast! It is a very three-dimensional piece with great composition! These specimens are rare, and hard to obtain in good quality and size like this, which is a truly high level specimen in any competitive or Tsumeb collection. Ex. Kurt Hefendehl collection.