This is a lovely miniature specimen of the rare zinc arsenate mineral Legrandite from perhaps its best known locality - Ojuela mine, in Mexico. The Legrandite forms vivid acidic bright lemon-yellow crystals in parallel alignment in a chocolate-brown limonitic gossan matrix. There are very few terminations due to the way the Legrandite has spanned a cavity, but the defining feature is the length of the crystals at over 2 cm and the overall coverage. This is undoubtedly a very rich example of Legrandite.
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