In 1959, King Rama 9 visited Phuket and witnessed the tin mining business of Anuphas and Sons Co., Ltd., he then asked that Thailand should also have a smelting plant to increase raw material value for trade with USA, England and other countries in Europe. Thai Smelting and Refining Co., Ltd. then established known as THAI SARCO and for exporting refined tin, all tin mines are to be using this refinery.

ThaiSarco is one the biggest refinery in Thailand, established on 8th May 1963 and on 6th September of the same year has been awarded a reinvestment and subject to refine pure tin of 15,000 tons each year. Where trade is to be conducted as commodities the same way as in Malaysia and referred to daily market price based from Penang, Malaysia, later changed to Kuala Lumphur.