Harmonized System
U.S. imports of Refractory Ceramic Goods Containing Over 50% Free Carbon (HS 690310) totaled $2.4M in August 2026, imported from 21 countries.
Importers of Refractory Ceramic Goods Containing Over 50% Free Carbon paid $53K in duties in August 2026, an average duty rate of 2.16% — duty actually collected as a share of the imports that cleared customs, not the published tariff schedule.
Last updated: August 2026 dataCarbon-dominant refractories — typically graphite or carbon-bonded shapes used in blast furnace hearths, electric arc furnace sidewalls, and aluminum smelting cells — are classified here when free carbon exceeds 50% by weight. The entire heading resolves to a single 10-digit line (6903100000), simplifying classification but placing the analytical burden on accurately measuring free carbon content versus combined carbon. Mexico and Japan are the leading sources of US imports under this heading. Importers should be aware that Chinese-origin carbon refractory goods may be subject to Section 301 tariffs, and that antidumping or countervailing duty orders on carbon products from specific origins warrant verification before entry.
AI-written summary of the official U.S. Census Bureau trade figures on this page — verify before relying on it.
370 import shipments a month
Free carbon refers to elemental carbon — graphite or amorphous carbon — present in the ceramic matrix as a distinct phase, as opposed to carbon chemically combined in carbides such as silicon carbide. Laboratory analysis (typically by combustion or acid-dissolution methods) is used to quantify free carbon content. If the free carbon content does not exceed 50% by weight, the article would be classified elsewhere in heading 6903.
The primary consumers are steel producers (blast furnace hearth linings and tap-hole blocks), aluminum smelters (cathode blocks and sidewall linings), and electric arc furnace operators. These applications require the combination of high thermal conductivity, resistance to molten metal attack, and dimensional stability that carbon-bonded and graphite ceramics uniquely provide.
Subheading 3 of 3 in heading 6903
Subheading 690310 · $2.4M of $37.6M
Trade Directory
List your company under HS 690310 — Refractory Ceramic Goods Containing Over 50% Free Carbon, so the companies trading it can find you. Be the first supplier listed.
HS10 import codes under this HS6 parent, each with its own page. Source: U.S. Harmonized Tariff Schedule.
| Code | Description | Imports for consumption | Average duty rate | Dutiable Share | Duty Collected |
|---|---|---|---|---|---|
| 6903100000 | Oth Refrac Ceramic Gds W Graphite/Carbon Ov 50pct | $2.4M | 2.16% | 17.83% | $53K |
HS10 export codes under this HS6 parent, each with its own page. Source: U.S. Schedule B export classification.
| Code | Description | Export Value |
|---|---|---|
| 6903100000 | Oth Refrac Ceramic Gds W Graphite/Carbon Ov 50pct | $2.9M |
Import lines come from the U.S. Harmonized Tariff Schedule and export lines from Schedule B. The two are numbered by different agencies, so the same 10-digit code can appear in both tables describing a different product.
ImportsExports
Imports
$2.4MYoY · free account
Exports
$2.9MYoY · free account
12-mo low · imports
Low · free accountOver the twelve months to August 2026, the U.S. imported $25.9M of Refractory Ceramic Goods Containing Over 50% Free Carbon and exported $23.0M.
Through August 2026. Source: U.S. Census Bureau.
Imports · August 2026
origin
Mexico and Poland together supply 88% of it. China pays 35.4% duty; Mexico 0.0%.
customs district
entry
rate provision · imports
82.2% enters free of duty; duty collected equals 2.16% of imports for consumption.