In the realm of pseudomorphs, 'double replacements' are uncommon. The most famous of these is rosasite replacing malachite, which had previously replaced azurite. Such specimens are well-known from the Tsumeb Mine, and rarely elsewhere. This double substitution example is from a surprising (but reasonable) locality: the Ojuela Mine. It consists of partial to complete rosasite blades to a few mm in size rising from matrix. Where broken, a malachite core is revealed (under magnification). The shape is strongly suggestive of an azurite origin (compare with these Tsumeb Mine examples). An uncommon - if not unique - specimen; of the 3783 Ojuela Mine mineral specimen photos posted at Mindat, none mention this replacement. Minor calcite is also present.