He sent samples of his salts back to Europe but his claim was disputed by French chemist, Collett-Desotils who claimed the element was an impure chromium sample. Del Rio decided he must have been incorrect and withdrew his claim. In another 30 years, Swedish chemist Nils Gabriel Sefström would rediscover Del Rio's erythronium. He named it vanadium, after the Norse goddess of beauty and fertility, Vanadis.
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