Juan José Elhuyar Lubize (15 June 1754 – 20 September 1796) was a Spanish chemist and mineralogist, who is best known for being first to isolate tungsten with his brother Fausto Elhuyar in 1783.He was born in Logroño, in northern Spain and died in Santafé de Bogotá, New Granada (present-day Colombia) at 42.