Clays contain large amounts of trace minerals. It is common to see as 
many as 75 different trace minerals in Montmorillonite clays.
  green clay soap
green clay soap 
Medicinal clay is typically available in health food stores as a dry 
powder, or in jars in its liquid hydrated state - which is convenient 
for internal use. For external use, the clay may be added to the bath, 
or prepared in wet packs or poultices for application to specific parts 
of the body. Often, warm packs are prepared; the heat opens up the pores
 of the skin, and helps the interaction of the clay with the body.
Green clay, also known 
as illite, is an organic material comprised of a host of essential 
minerals, iron oxides, and decomposed plant material such as kelp and 
seaweed. Illite was called French green clay for centuries, named after 
the rock quarries in the south of France that yielded most of the 
world's illite deposits. The clay is truly green in color; the more it 
leans toward gray-green, the less valuable it is deemed. Green clay is 
used in alternative medicine, both externally and internally, for many 
reasons, but mostly for cleaning and detox because of its vast absorbent
 properties. Illite is also used to relieve menstrual cramps, morning 
sickness, diarrhea, indigestion, and heartburn
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