Minerals, availability & digestion

Eugene F. Monaco EFMonaco at compuserve.com
Sun Sep 21 07:34:56 EDT 1997

>Know your rock type, don't choose mono minerallic rocks such as quartz
thinking they will contain a broad range of minerals. Ask a geologist or
your quarry manager what the rock type is and access material which has
the consistency of talcum powder. The finer the powder the greater the
surface area that can be attacked by soil acids.

It seems to me that most of the batholithic rocks: granite (and gneiss) and
bassalt tend to have a broad spectrum of minerals in them.  The sedimentary
rocks such as sandstones, limestones and dolomites, and shales, have less
of the spectrum.  To be sure, limestones and dolomites are primarily
calcium and magnesium carbonates; sandstones are going to be mostly quartz
which is basically silicon dioxide.  The finest talcs are gypsum
precipitates.  You can go to any construction site and get all the gypsum
board waste you want.  Does any one know how gypsum is useful?

The silica in quartz might be available for flax given the right soil life
guild.  I know from my herbology that whole flax seeds are high in silica
which has been phyto-synthisized for maximum availability, meaning it has
bonded with the amino acids in the plant somehow and is better available
for absorbtion in our small intestines.  Contrast that with eating a
handful of sand.

A sidenote on trace minerals.  Somehow clays (perhaps someone can explain
this) manage to have  70 some trace minerals, with maybe a lot of iron or
magnesium.  Although there doesn't seem to be shortage of clay in the soils
here in Tennessee, I could imagine that in sandier locations there would be
less.  Anyhow, although certain wild herbs no doubt accumulate these trace
minerals (which is irrelevant to agriculture because the population doesn't
eat wild herbs, nor does the livestock), and deer certainly eat the wild
herbs all the time, even this is not enough for the deer.  I took a course
last winter where we studied wild scat.  The instructor (Tom Brown, Jr.)
showed us some deer scat he found which was solid clay (he had actually
fired some in a kiln), they looked like oval-shaped musket balls (not
muscrat) from the American civil war.  The idea is that the deer find these
mineral licks, and they lick so much that it works its way through their
digestive and intestinal systems in enough volume to come out solid clay,
not mixed with roughage and greens (mustard, mints) which you usually find
in deer scat.  No I'm not a scatologist.  My guess is that the deer's
intestinal system is not much better than our's in being able to absorb
inorganic minerals; but their instinct as to their need for the trace
minerals tells them to lick quite a lot at one sitting.  Takes a licking
and keeps on shitting.  Pretty amazing eh?

Mollison talks about geophagy (sp?), the eating of dirt, in his Human
Nutrition book.

Gene Monaco
East Tennessee Permaculture  (EFMonaco at compuserve.com)
Herbs, consultations, & training for total health and environmental
PO Box 11851, Knoxville, TN  37939      (423) 457-4354

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