For clays and silts the usual classification is derived from their
engineering properties under varying conditions of moisture.
The Atterberg limits are an empirically developed but widely
used procedure for establishing and describing the consistency
of cohesive soil. The Atterberg limits are of a somewhat
empirical nature, but frequently these limits to provide useful
information regarding soil strength, behavior, stability, type,
and state of consolidation, or classification of a clay as organic
or inorganic. Consistency limits of soil have been determined in
the clays occurring as a result of weathering Upper Cretaceous
aged andesitic rock and are given in Table 2. These samples
have been defined normally consolidated high plasticity soil.