Siliceous fossil meals (e.g. kieselguhr, tripolite and diatomite) and similar siliceous earths; whether or not calcined, of an apparent specific gravity of 1 or less
In plain English
This category includes siliceous fossil meals, such as kieselguhr, tripolite, and diatomite, along with similar siliceous earths. These materials may be calcined or uncalcined, provided they have an apparent specific gravity of 1 or less. The classification does not further divide these goods into separate subcategories.
6-digit subheadings (1)
Official HS 2022 subheading texts. National tariff schedules subdivide these further (8-10 digit lines) and set the actual duty rates.
Siliceous fossil meals (e.g. kieselguhr, tripolite and diatomite) and similar siliceous earths; whether or not calcined, of an apparent specific gravity of 1 or less
Chapter 25 classification notes
Frequent misclassification in this chapter
Worked marble / granite goes to Chapter 68 (articles of stone) not 25; raw blocks stay in 25.
Classification certainty
The 6-digit level shown here is the internationally harmonised layer. Duty rates attach to national 8-10 digit tariff lines, which differ by country — use the duty calculator for lane estimates. For binding certainty, request a ruling from the destination customs authority.
Binding tariff ruling databaseOther headings in Chapter 25
- 2501 — Salt (including table salt and denatured salt); pure sodium chloride w…
- 2502 — Iron pyrites; unroasted
- 2503 — Sulphur of all kinds; other than sublimed, precipitated and colloidal …
- 2504 — Graphite; natural
- 2505 — Sands of all kinds; natural, whether or not coloured, other than metal…
- 2506 — Quartz; (other than natural sands), quartzite, whether or not roughly …
- 2507 — Kaolin and other kaolinic clays; whether or not calcined
- 2508 — Clays; (not including expanded clays of heading no. 6806), andalusite …
- 2509 — Chalk
- 2510 — Natural calcium phosphates; natural aluminium calcium phosphates and p…
- 2511 — Natural barium sulphate (barytes); natural barium carbonate, (witherit…
- 2513 — Pumice stone; emery; natural corundum, natural garnet and other natura…
- 2514 — Slate, whether or not roughly trimmed or merely cut, by sawing or othe…
- 2515 — Marble, travertine, ecaussine and other calcareous stone; of an appare…
- 2516 — Granite, porphyry, basalt, sandstone, other monumental and building st…
- 2517 — Pebbles, gravel, crushed stone for concrete aggregates for road or rai…
- 2518 — Dolomite, whether or not calcined or sintered, including dolomite roug…
- 2519 — Natural magnesium carbonate (magnesite); fused magnesia; dead-burned (…
- 2520 — Gypsum; anhydrite; plasters (consisting of calcined gypsum or calcium …
- 2521 — Limestone flux; limestone and other calcareous stone, of a kind used f…
- 2522 — Quicklime, slaked lime and hydraulic lime; other than calcium oxide an…
- 2523 — Portland cement, aluminous cement (ciment fondu), slag cement, supersu…
- 2524 — Asbestos
- 2525 — Mica, including splittings; mica waste
- 2526 — Natural steatite; whether or not roughly trimmed or merely cut, by saw…
- 2528 — Natural borates and concentrates thereof (whether or not calcined), bu…
- 2529 — Feldspar; leucite; nepheline and nepheline syenite; fluorspar
- 2530 — Mineral substances not elsewhere specified or included