Elongated vanadinite crystals from Mibladen, Morocco (field of view about 25 mm), possibly due to incorporation of arsenic into the crystal lattice ("endlichite", as part of the solid solution series vanadinite-mimetite)
<a href="//commons.wikimedia.org/wiki/User:Klaproth" title="User:Klaproth">Klaproth</a>
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<span class="int-own-work" lang="en">Own work</span>