Amendment of excise duties updates the excise levy framework under the Sixth Schedule, altering additional excise provisions. The Finance Act, 2001 amends the Additional Duties of Excise (Goods of Special Importance) Act, 1957 by specifying operative alterations to the Central Excise Tariff and related charging provisions in the Sixth Schedule, thereby varying the earlier enactment's scope and application of additional duties of excise.