Essential character test classifies investment powder as refractory composition, not gypsum plaster, for jewel mould casting.

Imported investment powder used for investment casting of jewel moulds was held to be classifiable under Chapter 3816 as a refractory composition rather than under Chapter 2520.20 as plaster. The decisive factor was the product's composition and essential character: silica was the predominant component, while gypsum acted only as a binder. Chapter 2520.20 applies to gypsum and plasters derived from gypsum, whereas Chapter 3816 covers refractory cements, mortars, concretes and similar silica-based refractory compositions used for dental or jewel moulds. On this basis, the goods were correctly treated as refractory material, in favour of Revenue.

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Issues: Whether the imported investment powder was classifiable under Chapter 2520.20 as plaster, or under Chapter 3816 as a refractory composition.

Analysis: The product was used in investment casting for jewel moulds. The material composition showed silica as the predominant component, with gypsum functioning only as a binder. Chapter 2520.20 covers gypsum and plasters derived from gypsum, whereas Chapter 3816 covers refractory cements, mortars, concretes and similar compositions, including silica-based refractory compositions used for dental or jewel moulds. On the facts and composition of the product, silica gave the goods their essential character, and the goods were more appropriately treated as refractory material.

Conclusion: The product was correctly classifiable under Chapter 3816 and not under Chapter 2520.20, in favour of Revenue.

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