This specimen shows a very rich group of small micaceous crystals of tyuyamunite, brilliant and intense yellow color, contrasting on the matrix. The piece was labeled as francevillite, but we have performed SEM-EDS analysis that refers to the tyuyamunite species. The results indicated the presence of uranium, calcium, vanadium, and few silicium, thus move away from the francevillite containing barium and lead, together with vanadium and uranium. Results will be send to the buyer. From a Spanish mine not well represented in collections.

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