Xikuangshan mine (simplified Chinese: 锡矿山; traditional Chinese: 錫礦山; pinyin: Xīkuàngshān) in Lengshuijiang, Hunan, China,[1] contains the world's largest deposit of antimony.[2] It is unique in that there is a large deposit of stibnite (Sb2S3) in a layer of Devonian limestone. There are three mineral beds which are between 2.5 and 8 m thick which are folded in an anticline that plunges to the south-west. The total mineralised area of the mine has a surface extent of 14 km2. There are two different units at the mine, the northern one produces mixed oxide and sulfide such as stibiconite (Sb3O6(OH)) and the southern one produces stibnite. Ore is concentrated and refined on site in a refinery with a capacity of 10,000 tonnes of antimony per year.[3]