text: In 1805 del Río established an ironworks at Coalcomán. After overcoming numerous obstacles, he produced the first iron in Mexico, on 29 April 1807. Four years later, during the Mexican War of Independence, the royalists destroyed the ironworks. The iron he produced was superior to the celebrated imported iron from Biscay (Vizcaya), Spain.
  Del Rio was bitter about Humboldt's mistake in not confirming the discovery of vanadium, and strongly reproached him.
  He continued to teach at the College of Mines until his death, a course that "could well have been taught at the Polytechnic school in Paris", according to Michel Chevalier, who visited del Río shortly before the latter's death.