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Criteria for Selecting a Clay - by PerryA~

There are ten things you should ask of any clay you are considering for topical or internal use for health purposes.


  1. Is it a Calcium based Bentonite?

  2. Is the clay milled to at least a 325 screen mesh particle?

  3. Is the pH at least 8.5-9.9? The higher the better?

  4. Is it a clay that absorbs and adsorbs, a Living Clay capable of changing and exchanging ions? 

  5. Is it a green swelling clay of the Montmorillonite/Smectite group?

  6. Is it tasteless and odorless?

  7. Is its efficacy, its ionic charge ratio at least 20 to 1? (Drawing power)

  8. Is it an all natural clean clay direct from the mine source and not later processed or purified?

  9. Is it a clay from a mine protected from the elements?

  10. Is it a clay that expands to a 3 to 1 ratio in volume?  (Three part water to 1 part dry clay.)




It is critical when you ingest clay that it be Calcium based as opposed to Sodium based.  Demand from any clay company that you be given a copy of the MSDS sheet and a copy of the Mass Gas Spectrometer Test results.  These two documents will give you the specific mineral composition of their clay.  Any company who refuses to give you this data is hiding something from you.


Most Sodium Bentonite is suitable for commercial and industrial uses such as sealing farm ponds, sealing asphalt and in oil rig mud pits.


A good quality Calcium Bentonite Clay should contain the following as its top three minerals in about the following percentages:



Silica oxide

  Calcium Oxide 28-10%
  Magnesium Oxide 14-12%


In addition it should contain no more than 2% in sodium.  One popular Sodium Bentonite contains 29% sodium!  When doing a cleanse, detox or tackling any health related issue, the last thing you want to do is to ingest substantial amounts of salt.


It is also important that the clay be pure, clean and natural and direct from the source mine - a subsurface mine has been protected from the natural elements. Most clays that claim to be 100% pure have been cleaned using either a heat process or a hydration process to “wash” out impurities. 


Both processes can take a 95% pure clay to a “100%” pure state, but in doing so reduces the efficacy from around 15 to 1 down to 5 to 1.  In their attempt to make a purity claim they are actually destroying the natural healing properties.  Read labels carefully for any notation of the clay having been cleaned, processed, filtered, recharged or tampered with in any fashion other than milling.


Clays are all milled to some degree of “fineness.”  This fineness number typically runs from 50 to 325 screen mesh. A 50 screen mesh feels like fine grain sand while a 325 mesh is almost as fine as talcum powder.  The finer the mesh the better the milling process and in turn the better it hydrates when water is added.  Suspension as a colloidal is cleaner, quicker and more highly charged.  If taken internally in a capsule form it is imperative that Calcium Bentonite Clay be screened to at least a 325 mesh so that it assimilates into a colloidal in the shortest time possible after ingestion.  I recommend you not buy any Calcium Bentonite Clay that is milled to less than a 325 screen mesh.


The pH of your Calcium Bentonite Clay is crucial.  One of its greatest blessings to your health is its ability to increase your pH from acid to alkaline.  While all clays are alkaline, only 2-3 are 9.5 to 9.7 in their natural state.  I recommend you select a Calcium Bentonite Clay with the highest pH available.


Naturally you want a tasteless, odorless clay that is creamy smooth when hydrated. Unprotected clays tend to pick up odors. Be wary of clays with strong odors.


Lastly, and of paramount importance is a clay’s efficacy rate – how well it works. This piece of information is provided in a ratio from such as 10 to 1. This means the following.  A clay with a 10 to 1 efficacy rating removes 10 times it’s molecular weight in positive charged ions from your body.  By contrast, a clay with a 3 to 1 efficacy rating would remove 3 times its molecular weight in positive charged ions (the bad stuff that attacks our bodies).  In this example a 10 to 1 ratio when compared to a 3 to 1 ratio means the first clay would be over 3 times as effective as the second.


These clays capable of exchanging ions are called Living Clays or Active clays. Clays ability to absorb and adsorb directly effect their efficacy rate. Green swelling clays from the Montmorillonite/Smectite group are known as healing clays because of this trait.


There are only a few clays on the market today with an efficacy ratio greater than 12 to 1.  A few natural Calcium Bentonite Clays have a 31 to 1 ratio.  I recommend you read the literature carefully and call the company reps to find the specifics on a clay. If they don’t know the efficacy rate and mineral content, I would consider it a doubtful source.


Remember, the purpose of clay when used on a daily basis is to continually remove positive charged ions – the things that attack our body – from every cell in your body.  The very best clay to accomplish this goal is a pure, direct from the mine, natural Calcium Bentonite Clay with a pH of 9.0-9.7, a screen mesh of 325 and an efficacy of at least 30 to 1.


That being said, knowing what clay to use becomes the paramount question.  I've looked at two clays, and swore by looking at them they were same... And yet, the swelling properties were quite different, as were the tastes.


Keep in mind that not all Calcium Bentonites swell. If you really want a good guideline, you can actually acquire a sample of various clays, find and/or hire a BodyTalk System Practitioner to test your body's response to each clay. Most information on clay is from personal experience stories handed down through time.



PerryA~ is the owner of Nature's Body Beautiful:



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