The U.S. Natural Resources Conservation Service has a good guide for
assessing soil texture - sand, silt, clay, loam, and variations:

http://soils.usda.gov/education/resources/lessons/texture/

Apologies for cross-posting.


Allen Dart, RPA
State Cultural Resources Specialist/Archaeologist
USDA Natural Resources Conservation Service
Arizona State Office
230 N. 1st Avenue Suite 509
Phoenix AZ 85003-1723   USA
    602-280-8787 desk, 602-280-8809 fax
    [log in to unmask]

Executive Director
Old Pueblo Archaeology Center
PO Box 40577
Tucson AZ  85717-0577   USA
    520-798-1201 office, 520-798-1966 fax
    Email: [log in to unmask]
    URL: www.oldpueblo.org
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