| 2506 | | Quartz (other than natural sands); quartzite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape: | | | | |
| 2506.10.00 | 10 | Sands (other than natural) containing by weight 95 percent or more of silica and not more than 0.6 percent of oxide of iron | t | | | |
| 2510 | | Natural calcium phosphates, natural aluminum calcium phosphates and phosphatic chalk: | | | | |
| 2511 | | Natural barium sulfate (barytes); natural barium carbonate (witherite), whether or not calcined, other than barium oxide of heading 2816: | | | | |
| 2511.10 | | Natural barium sulfate (barytes): | | | | |
| 2511.20.00 | 00 | Natural barium carbonate (witherite) | kg | Free | | 30% |
| 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: | | | | |
| 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: | | | | |
| 2519.10.00 | 00 | Natural magnesium carbonate (magnesite) | t | Free | | $10.33/t |
| 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 |
| 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: | | | | |
| 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 | | | |
| 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% |
| 2611.00 | | Tungsten ores and concentrates: | | | | |
| 2618.00.00 | 00 | Granulated slag (slag sand) from the manufacture or iron or steel | t | Free | | 10% |
| 2619.00 | | Slag, dross (other than granulated slag), scalings and other waste from the manufacture of iron or steel: | | | | |
| 2620 | | Slag, ash and residues (other than from the manufacture of iron or steel), containing arsenic, metals or their compounds: | | | | |
| 2620.60 | | Containing arsenic, mercury, thallium or their mixtures, of a kind used for the extraction of arsenic or those metalsor for the manufacture of their chemical compounds: | | | | |
| 2620.60.10 | 00 | Of a kind used only for the extraction of arsenic or the manufacture of its chemical compounds | kg | 5% | Free (A+,AU,BH, CA,CL,D,E,IL,J, JO,MA,MX, P,SG) | 25% |
| 2620.91.00 | 00 | Containing antimony, beryllium, cadmium, chromium or their mixtures | kg | Free | | 30% |
