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macaloid & bentonite

updated sat 25 may 02

 

Tom Buck on fri 24 may 02


Vince:
according to my chemical dictionary, bentonite is a "colloidal
clay" (aluminum silicate) containing either sodium montmorillonite
(Wyoming or western bentonite) or calcium montmorillonite (southern
bentonite). the first is "swellable", the second does not swell when mixed
with water.
The dictionary lists Macaloid as a tradename for a magnesium
montmorillonite. in my view that makes them not identical. however, as you
noted, Macaloid behaves much as does the swellable bentonite. so from the
potter's viewpoint, Macaloid and the tradenamed bentonites can be used
interchangeably. If you need a "high white" material, then Macaloid would
be your choice.
til later. Peace. Tom (B).

Tom Buck ) -- primary address. "alias"
or secondary address.
tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street, Hamilton ON L8T 3E1 Canada