Refined tin shipments from Indonesia, the world’s top exporter, soared 62 percent in August from a month earlier as traders took advantage of rising prices and volume on the domestic exchange surged. Exports jumped to 5,379 metric tons from 3,313 tons in July, according to Trade Ministry data released Thursday. That’s the biggest increase in percentage terms since April, according to ministry data compiled by Bloomberg. The country didn’t ship any tin in August last year when a new rule was introduced ordering exporters to obtain permits. Tin, used in solder for electrical circuits, has advanced 35 percent in 2016 as demand outstrips supply, and is the best performer after zinc on the London Metal Exchange. The price slump at the start of the year and tight government regulations have prompted smelters in Indonesia to curb shipments. “Monthly volume is about in line with the consensus view of Indonesia’s annual production around or a little above 60,000 tons,” Peter Kettle, markets manager at ITRI Ltd., a U.K.-based research company, said by e-mail after the data were released. Tin for delivery in three months added 0.3 percent to $19,600 a ton on the LME on Thursday. Environmental Concerns Indonesia raised purity standards in July 2013, and in August that year the government ordered dealers to trade tin ingots on the Indonesia Commodity & Derivatives Exchange before shipment. Environmental concerns have taken their toll too. In February, the second-biggest smelter, PT Refined Bangka Tin, said it had ceased operations on environmental grounds, while PT Timah halted offshore mining in January in response to complaints from fishermen. Trades on the local exchange jumped 79 percent to 1,319 lots, or 6,595 tons in August, from 738 lots in July, exchange data show. The country shipped tin to more than a dozen countries last month, with Singapore taking 65 percent of the total, according to ministry data, based on surveyors’ reports prior to shipment. Exports in the first eight months fell 16 percent to 38,343 tons from a year ago, according to Bloomberg calculations.