(2)In the case of high strength ordinary portland cement conforming to specification No. IS 1818/1976 an additional price of Rs. 12 per metric tonne may be added and an additional amount of Rs. 20 per metric tonne for every increase in the compressive strength at 100 kg. per sq. cm. or part thereof may also be added wherever there is such an increase in the compressive strength over the said specification.
