china molybdenum company limited (simplified chinese: 中国钼业; traditional chinese: 中國鉬業 or simplified chinese: 洛阳栾川钼业; traditional chinese: 洛陽欒川鉬業, sehk:3993, sse: 603993) is the largest molybdenum producer in mainland china and top 5 in the world listed in the hong kong stock exchange and shanghai stock exchange. it is one of the largest tungsten producers in the world, and is the second largest cobalt and niobium producer and the leading copper producer worldwide. the headquarters of the company is at luanchuan county, luoyang city, henan province. the chairman is mr. li chaochun (chinese: 李朝春).