If the clay is a montmorillonite or bentonite, then it is most likely that all of the aluminum oxide is actually bound to Silica, via the oxygen bond common to both.
However, using the ME-ICP method of analysis, which is the industry standard, there is no way to absolutely tell.
In other words, it is possible that only 99% of the aluminum oxide is part of the actual clay and bound in crystal form. The clay itself is an aluminum silicate. But, with some clays, there might actually be aluminum contamination from the surrounding soil/ocean water/rain leaching. If aluminum from the soil mixed with the clay due to natural weathering, then it too would test as an aluminum oxide.
With sedimentary clays, such as most of the deposits in France, there is a greater risk of trace metal and mineral "contamination" (using the word in a scientific sense, not in a "toxic" sense). Clay deposits which have not been protected from the climate have a far greater mineral content, and a far greater variety of possible undesireable elements.
I do not believe that you are bringing harm to yourself by ingesting reasonable amounts of French Clay.
I'm trying to work on finding a way to determine these things accurately using science. You might be surprised to find out that when I send clay to different labs for analysis, I get completely different "results" for the same exact sample. Luckily, I have a friend who is a very capable clay scientist who is usually able to tell me why Lab X and Lab Y made mistakes reading the results.
The first step is to accurately determine what the substance actually is. In France, there are two primary forms of green clay used in natural medicine: French Montmorillonite and French Illite. The aluminum found in the montmorillonite is most likely nearly all crystalized and inert in the human body. I'm not certain if this is the case with the Illite, because the Illite is not a smectite clay, it is a mica... completely different.
Once the type of clay is identified, we then know how it is structured. Montmorillonites/Bentonites are minute crystals with a certain shape. The size of the crystals vary, but they are all made up of Silica Oxide crystals that owe there structure to a base metal. Most often, this base metal is from volcanic activity (either ash, or raw stone that has aged via aeons of "wear and tear").
The calcium montmorillonite we use is very special. For example, it is 44% silica dioxide... This is far less than most montmorillonites. Most of that 44% is going to be bound up with one other mineral, in all cases, that mineral is a metal.
The clay is 11.7% magnesium oxide. Therefore, since the clay is a smectite clay (as verified via SEM and TEM), it is safe to assume that there is a great deal of Magesium Silicate, where there would normally be aluminum silicate.
Next, the clay is 9.85% calcium oxide. Therefore, it is likely that there is an abundance of calcium silicate.
Then, 6.75% aluminum oxide.... 3.2% potassium oxide, 2.3% Ferrous oxide, and 1.5% sodium oxide.
35% of the materia is base metal content, with 44% silica. 19% was lost on ignition in testing, which makes 98% of the material reasonably accounted for, with 1.5% macro content of less signficant minerals (which I didn't list in this email) and about .5% trace minerals in the PPM to PPB range.
I'm not a clay scientist but I've been trying to study clays from a scientific viewpoint for many years, therefore I've been testing various therapeutic grade clay samples using as many methods as I can generally afford.
In our three clay blend, I use the cleanest clay I've tested, the calcium montmorillonite, the most potent detox clay I've tested, the green sodium bentonite from Wyoming, and the most well studied mineral supplement (and yet the "dirtiest"), the red california desert clay. I have strong reason to believe that none of these clays pose a risk for aluminum toxicity, but I haven't medically proven so as of yet.
Unfortunately, I cannot contrast the French clays with our clays as of yet, because the French companies have refused to give me any complete analysis of the their clays, and I first and foremost desire to study the clays in North America first. Hopefully by the time my next volume of work is published, I will have added the French clays to the growing list of clays I'm having lab work done on.
To close, I think that the folks at Frontier simply don't have the background to understand that most, if not all, of the aluminum oxide tested is part of the silica-oxide crystal matrix that forms the clay particles itself...
The cleaner the clay, the less chance that there is any leaching at all. Currently, I determine how clean a clay is by doing a full trace mineral analysis. I then add up the total sum to get an "end" number, and I compare them. But that doesn't mean that sedimentary clays, like the Californa desert clay, are bad or worse... This just gives me a baseline to try to understand the different effects, potentials, and dynamics of different clays. I hope in the future that continued studies will reveal increasingly more useful information.
Kind Regards,
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