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Re: Re: What's the truth about laterite

> Date: Mon, 3 May 1999 22:52:52 -0600 (MDT)
> From: "Roger S. Miller" <rgrmill at rt66_com>
> Subject: Re: What's the truth about laterite
> Laterite is a type of soil that forms in tropical climates.  Canada and
> the upper 49 states of the US are not currently in tropical cimates and as
> a result there are no *recent* soils in the 49 upper states or Canada that
> can truly be called laterites.
> >From the point of view of a soil scientist that is the same thing as
> saying that there are no laterites in the US (aside from Hawaii) or
> Canada.
> However...  all of North America has been in tropical climates at times in
> the geologic past and there are areas in North America where small inliers
> of ancient soils are preserved as rocks.  Some of those ancient soils
> happen to be laterites.  The most well-known of those are probably the
> bauxite deposits in Arkansas, but there are other areas as well.  In all
> cases I think the ancient laterites are rocks and not something a soil
> scientist is going to get worked up about.  They're definitely in the
> geologists' domain.

Ohh, I am playing catch up here..
Thank you Roger for your informative, unemotional, and unbiased post!
Another thing I was told by a soil scientist was that laterite takes
around a million years of constant tropical heat and rain to form in the
first place. So the current laterite in todays tropics are at least a
million years old, while those remant rocks in north america are
obviously much older. 
> > Why aren't people concerned about this?
> >From comments I've read it appears that the users of Substrate Gold are
> mostly happy with the product, regardless of whether it's a true laterite
> or something else.  If it does what it's claimed to do, then there isn't
> much reason to be concerned.

Well I guess if I want to make my own laterite, I will have to get a
pick axe and ground up some rocks...

Robert H