Salt; sulfur; earths and stone; plastering materials, lime and cement

The 29 headings of chapter 25

• 2501: Salt (including table salt and denatured salt) and pure sodium chloride, whether or not in aqueous solution or containing added anti-caking or free-flowing agents; sea water (1 code, General duty Free)
• 2502: Unroasted iron pyrites (1 code, General duty Free)
• 2503: Sulfur of all kinds, other than sublimed sulfur, precipitated sulfur and colloidal sulfur (2 codes, General duty Free)
• 2504: Natural graphite (3 codes, General duty Free)
• 2505: Natural sands of all kinds, whether or not colored, other than metalbearing sands of chapter 26 (3 codes, General duty Free)
• 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 (4 codes, General duty Free)
• 2507: Kaolin and other kaolinic clays, whether or not calcined (1 code, General duty Free)
• 2508: Other clays (not including expanded clays of heading 6806), andalusite, kyanite and sillimanite, whether or not calcined; mullite; chamotte or dinas earths (8 codes, General duty Free)
• 2509: Chalk (2 codes, General duty Free)
• 2510: Natural calcium phosphates, natural aluminum calcium phosphates and phosphatic chalk (2 codes, General duty Free)
• 2511: Natural barium sulfate (barytes); natural barium carbonate (witherite), whether or not calcined, other than barium oxide of heading 2816 (3 codes, General duty Free, some per unit)
• 2512: Siliceous fossil meals (for example, kieselguhr, tripolite and diatomite) and similar siliceous earths, whether or not calcined, of an apparent specific gravity of 1 or less (1 code, General duty Free)
• 2513: Pumice; emery; natural corundum, natural garnet and other natural abrasives, whether or not heat-treated (4 codes, General duty Free)
• 2514: Slate, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape (1 code, General duty Free)
• 2515: Marble, travertine and other calcareous monumental or building stone of an apparent specific gravity of 2.5 or more, and alabaster, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape (4 codes, General duty Free to 3%)
• 2516: Granite, porphyry, basalt, sandstone and other monumental or building stone, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape (7 codes, General duty Free to 3%)
• 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 (7 codes, General duty Free)
• 2518: Dolomite, whether or not calcined or sintered, including dolomite roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape (2 codes, General duty Free to 3%)
• 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 (4 codes, General duty Free)
• 2520: Gypsum; anhydrite; plasters (consisting of calcined gypsum or calcium sulfate) whether or not colored, with or without small quantities of accelerators or retarders (2 codes, General duty Free)
• 2521: Limestone flux; limestone and other calcareous stone, of a kind used for the manufacture of lime or cement (1 code, General duty Free)
• 2522: Quicklime, slaked lime and hydraulic lime, other than calcium oxide and hydroxide of heading 2825 (3 codes, General duty Free)
• 2523: Portland cement, aluminous cement, slag cement, supersulfate cement and similar hydraulic cements, whether or not colored or in the form of clinkers (5 codes, General duty Free)
• 2524: Asbestos (7 codes, General duty Free)
• 2525: Mica, including splittings; mica waste (5 codes, General duty Free)
• 2526: Natural steatite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks or slabs of a rectangular (including square) shape; talc (2 codes, General duty Free)
• 2528: Natural borates and concentrates thereof (whether or not calcined), but not including borates separated from natural brine; natural boric acid containing not more than 85 percent of H3BO3 calculated on the dry weight (3 codes, General duty Free)
• 2529: Feldspar; leucite, nepheline and nepheline syenite; fluorspar (5 codes, General duty Free)
• 2530: Mineral substances not elsewhere specified or included (8 codes, General duty Free to 2.9%)

Where it sits in the schedule

Chapter 25 is in Section V of the Harmonized System, mineral products (chapters 25 to 27). Rates are those printed in the 2026 HTS Revision 23; Chapter 99 duties (Section 232, Section 301, IEEPA) are charged on top and are not included.