Excise duty exemption for jewellery reconversion limits duty to value addition and labour charged to the customer. Partial exemption from Central Excise duty applies where jewellery supplied by a retail customer is reconverted or precious stones supplied by a retail customer are mounted; duty is limited to the amount attributable to value addition, consisting of additional materials and labour charges charged to the retail customer, and manufacturers must maintain records identifying the customer, weights and purities, receipt and issue voucher details, and separately state value addition on the invoice.