ORDER 1. Having gone through the impugned judgment, we find that in these cases the differential duty was claimed by the Department on two grounds, namely, undervaluation and clandestine removal. 2. As far as undervaluation is concerned, the Tribunal has not examined the percentage of sales to unrelated buyers. According to the assessee the entire material was placed in that regard before the Commissioner, but unfortunately the Tribunal has not considered that material while deciding the question of undervaluation. 3. On the second ground of clandestine removal, the case of the Department is that zinc ingots were removed at the time of clearance in the guise of zinc metallic residue. This issue has also not been gone into by the Tribunal. 4. For the aforestated reasons, we set aside the impugned judgment of the Tribunal dated 6-1-2005 and remit the matters to the Tribunal for fresh de novo consideration of the entire matter in accordance with law. 5. The Department's civil appeals are accordingly allowed with no order as to costs.