Between 1773 and 1777, Elhúyar studied medicine, surgery and chemistry, as well as mathematics, physics and natural history with his brother Juan José Elhuyar in Paris.

During those years, he published numerous articles and dossiers about minerals, ways to extract and purify them, etc., which made him famous throughout Europe as one of the top experts on the subject.

He also collaborated with Joseph-Louis Proust, the famous French chemist at the service of king Charles IV of Spain, who directed the National Laboratory in Segovia.

During his tenure, he commissioned and directed the construction of that institution's seat, the Palacio de Minería, which was finished in 1813 and is considered one of the jewels of the Spanish American neoclassicism.

After falling from his ministry, he was appointed yet again General Director of Mines, and resumed his research activities in chemistry from this quieter office till his death in Madrid on January 6, 1833.