Additional excise duty on assessable textile goods imposed as a supplemental levy, excluding certain notification-based reliefs. The amendment imposes an additional duty of excise on Schedule goods chargeable under the Central Excises and Salt Act when assessed to duty, calculated as a percentage of the total amount chargeable. Notifications that provide exemptions, credits, or reductions equal to duties already paid on raw materials are excluded from affecting the basis for this additional duty, so such reliefs do not prevent imposition of the additional levy.