Special duty of excise imposed as surcharge on excisable goods, additional to existing duties and subject to excise rules. A special duty of excise equal to ten per cent of the amount chargeable is levied on goods chargeable under the Central Excises Act, excluding notifications that grant credit or reduction for duty already paid on inputs; this duty is additional to existing excise duties, ceases to operate after 31 March 1986 (with transitional savings), and is to be administered, so far as practicable, under the procedural provisions, refunds and exemptions framework of the Central Excises Act and its rules.