Grain Size Classification
 
Major Component
Of Sample
 
Size Range
 
Descriptive Term(s) (Of Components Also Present in Sample)
 
Percent of Dry Weight
 
Boulders
 
Over 8 in. (200mm)
 
Trace
 
1 - 9
 
Cobbles
 
8 in. to 3 in.
(200mm to 75mm)
 
Little
 
10 - 19
 
Gravel
 
3 in. to #4 sieve
(75mm to 2mm)
 
Some
 
20 - 34
 
Sand
 
#4 to #200 sieve
(2mm to .074mm)
 
And
 
35 - 50
 
Silt
 
Passing #200 sieve
(0.074mm to 0.005mm)
 
 
 
 
 
Clay
 
Smaller than 0.005mm