Common use of Gradation Clause in Contracts

Gradation. Sieve Sizes Percent Passing ½ inch (12.5mm) 100 3/8 inch (9.5 mm) 95 - 100 No. 4 (4.75 mm) 20 - 95 No. 8 (2.36 mm) 10 - 65 No. 30 (0.60 mm) 0 - 20