| 2513 |  | Pumice; emery; natural corundum, natural garnet and other natural abrasives, whether or not heat-treated: |  |  |  |  | 
| 2513.20 |  | Emery, natural corundum, natural garnet and other natural abrasives: |  |  |  |  | 
| 2517 |  | Pebbles, gravel, broken or crushed stone, of a kind commonly used for concrete aggregates, for road metalling, or for railway or other ballast; shingle and flint, whether or not heat-treated; macadam of slag, dross or similar industrial waste, whether or not incorporating the materials cited in the first part of the heading; tarred macadam; granules, chippings and powder, of stones of heading 2515 or 2516, whether or not heat-treated: |  |  |  |  | 
| 2517.10.00 |  | Pebbles, gravel, broken or crushed stone, of a kind commonly used for concrete aggregates, for road metalling, or for railway or other ballast, shingle and flint, whether or not heat-treated |  | Free |  | 30% | 
| 2517.20.00 | 00 | Macadam of slag, dross or similar industrial waste, whether or not incorporating the materials cited in subheading 2517.10 | t | Free |  | 30% | 
| 2519 |  | Natural magnesium carbonate (magnesite); fused magnesia; dead-burned (sintered) magnesia, whether or not containing small quantities of other oxides added before sintering; other magnesium oxide, whether or not pure: |  |  |  |  | 
| 2520 |  | Gypsum; anhydrite; plasters (consisting of calcined gypsum or calcium sulfate) whether or not colored, with or without small quantities of accelerators or retarders: |  |  |  |  | 
| 2523 |  | Portland cement, aluminous cement, slag cement, supersulfate cement and similar hydraulic cements, whether or not colored or in the form of clinkers: |  |  |  |  | 
| 2523.21.00 | 00 | White cement, whether or not artificially colored | t | Free |  | $1.76/t, including  weight of container | 
| 2528 |  | Natural borates and concentrates thereof (calcined or not), but not including borates separated from natural brine; natural boric acid containing not more than 85 percent of H3BO3 calculated on the dry weight: |  |  |  |  | 
| 2528.10.00 | 00 | Natural sodium borates and concentrates thereof (whether or not calcined) | kg | Free |  | Free | 
| 2529.21.00 | 00 | Containing by weight 97 percent or less of calcium fluoride | t | Free |  | 13.5% | 
| 2529.22.00 | 00 | Containing by weight more than 97 percent of calcium fluoride | t | Free |  | $5.51/t | 
| 2530.90.80 | 15 | Earth colors | kg |  |  |  | 
| 2601 |  | Iron ores and concentrates, including roasted iron pyrites: |  |  |  |  | 
| 2601.11.00 |  | Iron ores and concentrates, other than roasted iron pyrites: |  |  |  |  | 
| 2601.11.00 | 30 | Concentrates | t |  |  |  | 
| 2601.11.00 | 60 | Coarse | t |  |  |  | 
| 2602.00.00 |  | Manganese ores and concentrates, including ferruginous manganese ores and concentrates with a manganese con- tent of 20 percent or more, calculated on the dry weight |  | Free |  | 2.2¢/kg on  manganese content | 
| 2602.00.00 | 40 | Containing less than 47 percent by weight of manganese | kg Mn kg |  |  |  | 
| 2602.00.00 | 60 | Containing 47 percent or more by weight of manganese | kg Mn kg |  |  |  | 
| 2603.00.00 |  | Copper ores and concentrates |  | 1.7¢/kg on lead   content | Free (A,AU,BH, CA,CL,E,IL, J,JO, MA,MX, P,SG) | 8.8¢/kg on copper content +  3.3¢/kg on lead content +  3.7¢/kg on zinc content | 
| 2603.00.00 | 10 | Copper content | Cu kg |  |  |  | 
| 2603.00.00 | 20 | Lead content | Pb kg |  |  |  | 
| 2603.00.00 | 30 | Zinc content | Zn kg |  |  |  |