Cob: cast earth is for walls

[*Lootvik*]

Castearth uses calcined gypsum [plaster of paris] that causes the slurry to 
swell slightly as it cures.  This is supposed to prevent cracking, which 
you would ordinarily expect with such a wet mix.  Ligninsulfonate is used 
as a retarder to prevent the mix from going off before it's poured.  Of 
course you need forms for this method.  I'm sure it's far too low density 
to use as a countertop.

And then there's Paul with his cob machine.  Is it stored away collecting 
dust somewhere Paul?  ;-)

*Lootvik*