vietnam silica sand Suppliers & Manufacturers. Product/ServiceSilica Sand, Quartz Sand, Sio2 Sand, Silica Sand,,Silica Sand, Quartz Sand, Sio2 Sand, Silica Sand, Thach Ngoc Tin We are thach Ngoc Tin Co., Ltd, specialized in supply minerals such that diatomite, white sands (SiO2) for the companies that manufacture cement. can with large quntity resonable price and a range of sands.