Education
Leiden University.
Leiden University.
In 1936, he discovered the Ertsberg (English, "Ore mountain") on New Guinea that gave rise to the Grasberg copper mine. In 1939, he published an article about his find, but it was neglected due to World World War World War II Twenty years later, the article led to rediscovery of the Ertsberg and the development of the Ertsberg-Grasberg mine complex.