John O. Floyd asks if we are sure that the Munsell Soil Color Charts were
developed for soil colors.  The answer is yes.  An architect with whom I once
worked explained to me that the Munsell folks produce charts for a variety of
applications, and that he believed that they had begun with color charts for
paint and branched out from there.   I did once have a crew member bring an
enormous Munsell book, apparently designed for paint matching, into the field
as a joke.
 
My copy of the chart says that it is a soil color chart, and it includes the
"gley page," which covers those waterlain and anaerobic soils that I've only
encountered on several occasions.  The chart I use was definitely designed
for soil colors, probably with more input from soil scientists than from
archeologists, but I havent' seen that it's suffered from that.
 
When I get back from the field and begin analysis, I often find I have a
range of soil colors on field forms for the same area.  I  don't see any
problem with expressing soil color as a circumscribed range of colors, since
there are bound to be variations in nature as well as perception.
 
Some  of the problems people have experienced may stem from trying to use
soil color charts for other applications such as ceramic paste and glaze.
 This is compounded because differences in firing temperature and oxidation
will often cause color differences within the kiln (sometimes dictated by
which way the wind was blowing).  In the case of domestic redwares, there are
often extreme differences in color on the same vessel, and for the same
reasons.  Despite this, it can't hurt to have a consistent way to describe
those variations.
 
LJ Cook