Cob: Trouble finding fireclay

[Darel Henman]

Ryan Zwahr wrote:
> 
> Hi,
> Trying to build an earth oven per Kiko Denzer's book and I am having
> problems finding fireclay (a clay soil alternative that he suggests).  I
> live in Raleigh North Carolina, and I have a small lot and not really
> anywhere for digging my own clay soil, short of ripping up my grass in my
> yard, so I was trying to locate fireclay.  Nobody around here seems to know
> what it is or where to buy it.  I have tried contacting brickyards, ceramic
> and pottery supply stores, and the like.  Do you have any suggestions on
> brandnames or other names that it may be called by.  I did find some mason's
> cement, and portland cement at home depot, but I wasn't sure if they were
> the same thing.  Can someone steer me in the right direction?  Please be
> specific with the names of things I can use, since I am a "newbie" at this.
> Also if anyone has other suggestions as to a material I could use to cob
> with....
> 
> Thanks,
> Ryan Zwahr
> rzwahr at yahoo.com

Normal clay (pottery store have this) mixed with diatomaceus silica
(garden centers may have this, its often used to control ants),
sometimes called, diatomaceus earth, and water, should work fine.  Lime
may be added to this mix as well.  Experiement with little charcoal
burners.

Darel