Section 05 MINERAL PRODUCTS 25 Salt; sulphur; earths and stone; plastering materials, lime and cement 25 28 Natural borates and concentrates thereof (whether or not calcined), but not incl 25 28 00 25 28 00 00 Commodity Code Description 25 28 00 00 00 Natural borates and concentrates thereof (whether or not calcined), but not including bo