SINOMINE (HONGKONG) RARE METALS RESOURCES CO., LTD. is a wholly owned subsidiary of Sinomine Resources Group Co., Ltd. It owns the largest pollucite mine in the world. Its main business covers mining and processing of cesium, lithium, and tantalum ores; processing, leasing and sales of cesium brines including cesium formate. It has branches located in Canada, the United States, the United Kingdom and Norway. Its business extends to Europe, America, Asia and Africa. Due to the rarity of pollucite resources and high technical barriers in the industry, there are few companies in the world that can produce cesium products. Sinomine (Hongkong) has been the world leading cesium products supplier since the 1990s. It produces a complete range of high-quality cesium salts. Its processing technology and cesium formate quality are on the cutting-edge in the world. Cesium formate is mainly used in drilling and completion fluids in high-pressure/high-temperature oil and gas wells. The highly soluble cesium formate salt forms low-toxic high-density fluids with very low water activity. When used in drilling and completion applications they form low-viscosity, low-solids fluids that improve drilling efficiency, stabilize wellbores, reduce risk of well-control incidents, and minimize damage to the producing reservoir. To minimize chemical losses, cesium formate brine is supplied according to a leasing model, and valuable cesium formate brine is reclaimed from used fluids by specialized reclamation processes. Wells drilled and completed with cesium formate fluids have proven to be highly productive. Cesium formate drilling and completion fluids have been widely used in Europe, the Middle East, North Africa, Southeast Asia, South America and other regions.