HS Code for Refractory ceramic products

HS code 6903.90 is a residual category for refractory ceramic goods such as retorts, crucibles, muffles, nozzles, and plugs that do not meet the specific material requirements of subheadings 6903.10 (graphite/carbon) or 6903.20 (alumina/silica). These items are used primarily in metallurgical, chemical, and glass-making industries for handling molten materials. The classification is based on the refractory nature of the ceramic (resistance to high heat) and the specific shape or function of the article, provided it is not a brick, block, or tile. This category includes advanced ceramic compositions like silicon carbide, zirconia, or specialized nitrides. These products are often precision-engineered to withstand extreme thermal shock and chemical erosion from molten metals or acids. Because they are finished articles rather than construction materials, they are distinct from the bricks found in heading 6902.

Products Included

• Silicon carbide crucibles
• Zirconia nozzles for continuous casting
• Ceramic immersion tubes
• Refractory muffles for heat treatment
• Ceramic kiln furniture (setters and saggers)

Common Misclassification

This code is often confused with HS code 6902.90, which covers refractory bricks and tiles. The distinction is that 6903 is for laboratory or industrial "ware" (vessels, tubes, etc.) rather than structural "construction" goods. It is also sometimes confused with 6806, which covers mineral wools and expanded mineral materials used for insulation, which are not ceramic-bonded refractory articles.

FAQ

What is the HS code for refractory ceramic products?

The HS code for other refractory ceramic goods (like crucibles or nozzles) not containing graphite or high alumina/silica is 6903.90.

Are ceramic crucibles classified here?

Yes, if they are refractory and do not contain more than 50% graphite or alumina/silica, they fall under 6903.90.