>>>I'm currently looking at a ceramic assemblage from a late 18th-century
farmstead site in southeastern Connecticut and have come across a couple
of questions in the course of writing up the inventory. First, were
refined earthenwares ever salt-glazed and, if they were, how common a
practice was it and what were the firing techniques? Second, I've come
across several sherds of what I believe to be English white salt-glazed
stoneware but which have no glaze left on them.  They don't appear to be
obviously heat-altered as the paste shows no signs of burning - are
there any other taphonomic factors or use patterns which could account
for this condition?
 
 
   Re: salt glazed earthenwares: It won't work. Salt vaporizes at a much
higher temperature than earthenware clays can stand  (check Daniel Rhodes
"Clay and Glazes for the Potter" for the details). Unglazed stonewares can be
segments of english White SGSW (not too uncommon), but may also be Parian
ware, or some similar intentionally unglazed ware.