From code 7106 91 000:  Unworked gold or silver (only refined gold or silver in the form of ingots, plates, powder and granules, and gold used for coinage); unworked precious metals, including in powder form (except unique and non-refinable nuggets, refined precious metals in the form of ingots, plates, powder and granules); precious metals in the form of products and jewellery (except refined precious metals in the form of ingots, plates, powder and granules, as well as unprocessed forms). From code 7106: unworked precious metals (only unique and non-refinable  nuggets).