| 2523 | | Portland cement, aluminous cement, slag cement, supersulfate cement and similar hydraulic cements, whether or not colored or in the form of clinkers: | | | | |
| 2523.30.00 | 00 | Aluminous cement | t | Free | | $1.32/t, including weight of container |
| 2523.90.00 | 00 | Other hydraulic cements | t | Free | | $1.32/t, including weight of container |
| 2524.10.00 | 00 | Crocidolite (Blue) | t | Free | | Free |
| 2524.90.00 | 30 | Crudes | t | | | |
| 2524.90.00 | 40 | Milled fibers, group 3 grades (spinning fibers or equivalent) | t | | | |
| 2524.90.00 | 45 | Milled fibers, group 4 and 5 grades | t | | | |
| 2525 | | Mica, including splittings; mica waste: | | | | |
| 2525.10.00 | | Crude mica and mica rifted into sheets or splittings | | Free | | Free |
| 2526 | | Natural steatite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rect- angular (including square) shape;talc: | | | | |
| 2526.10.00 | 00 | Not crushed, not powdered | kg | Free | | 0.6¢/kg |
| 2526.20.00 | 00 | Crushed or powdered | t | Free | | 35% |
| 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 |
| 2528.90.00 | 10 | Natural calcium borates | kg | | | |
| 2529 | | Feldspar; leucite, nepheline and nepheline syenite; fluorspar: | | | | |
| 2529.21.00 | 00 | Fluorspar: | | | | |
| 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 |
| 2529.30.00 | | Leucite; nepheline and nepheline syenite | | Free | | Free |
| 2530 | | Mineral substances not elsewhere specified or included: | | | | |
| 2530.10.00 | 00 | Vermiculite, perlite and chlorites, unexpanded | kg | Free | | Free |
| 2530.20 | | Kieserite, epsom salts (natural magnesium sulfates): | | | | |
| 2530.90.10 | 00 | Natural cryolite; natural chiolite | t | Free | | Free |
| 2530.90.20 | 00 | Natural micaceous iron oxides | kg | 2.9% | Free (A,AU,BH,CA, CL,E,IL,J,JO,MA, MX,P,SG) | 20% |
Harmonized Tariff Schedule of the United States inquiry: 3203Ã
