Milpillas gave up so much azurite that, between 2012-2018 in particular, the market was flooded. And yet, each pocket and zone produced a different style. This variety of styles and combinations of colors is also what makes Milpillas as important as it was, and remains - not just for the quantity. This two-sided specimen looks totally different on each side. One side looks like a normal azurite with bright luster and unusually thick and chisel-like crystals, standing nicely on contrasting white matrix. Matrix specimens of this style with upright crystals on white rock are fairly uncommon, even despite the production here. The other side, however, shows off an ingrown spray of incredibly chatoyant, metallic-like, shimmering malachite that stands embedded in the azurite. This actually shows you the original crystal here was probably an azurite, replaced by the malachite, and later coated by a very thin second generation of azurite over the malachite - and this effect gives the electric neon azurite blue color to the other sides of the crystals. This series of pockets in one zone of the mine was later called the "electric blue" style of azurite, and it is thought that the color is indeed due to the optical properties of a micro thin layer of azurite deposited atop the malachite, to create a unique style compared to azurite from other locations. A very fine, interesting miniature from this classic discovery.