PERTH, May 21 -- Nyrstar NV, the world's largest zinc producer, said a fire at its Hobart smelter in Australia cut output by an estimated 20 percent.

The company is studying the damage and has no estimate on the cost, or when full production will resume, smelter general manager Jeremy Kouw said today by phone. No one was injured and government investigators are at the site, Kouw said.

The smelter, in the capital of Tasmania state, has a production capacity of 260,000 metric tons and exports mainly to Asia, according to the Balen, Belgium-based company's website. China consumes 41 percent of the word's zinc, used to rust-proof steel, Deutsche Bank AG estimates.

Zinc for three-month delivery rose 0.6 percent to $1,885 a ton on the London Metal Exchange at 1:56 p.m. Sydney time.

The Hobart smelter sources most of its metal from the Zinifex Century mine in Queenland state and Rosebery mine in Tasmania.