| 2521.00.00 | 00 | Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement | t | Free | | Free |
| 2522 | | Quicklime, slaked lime and hydraulic lime, other than calcium oxide and hydroxide of heading 2825: | | | | |
| 2522.20.00 | 00 | Slaked lime | kg | Free | | 0.3¢/kg, including weight of container |
| 2522.30.00 | 00 | Hydraulic lime | kg | Free | | 0.2¢/kg, including weight of container |
| 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 | Portland cement: | | | | |
| 2523.21.00 | 00 | White cement, whether or not artificially colored | t | Free | | $1.76/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 |
| 2525.20.00 | 00 | Mica powder | kg | Free | | 20% |
| 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 |
| 2529 | | Feldspar; leucite, nepheline and nepheline syenite; fluorspar: | | | | |
| 2529.10.00 | 00 | Feldspar | t | Free | | 49¢/t |
| 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 |