Rebecca K : Clay is where you find it! It is everywhere, and comes in all different types and grades. If you have seen the Red soil of the Tobacco Fields of Connecticut
You have been within feet of clay !
If you want to use
local materials any local Excavation Contractor will be a local soils expert and is just one phone call away.
Your local Highway Dept / Dept of Transportation knows exactly where rains cause the soils of roadside cuts to Swell and collapse down onto the road and exactly how
much manpower and equipment it will take to re-open a road and fix the roads drainage ditches ! Again a simple phone call away !
A simple google search will teach you how to determine if your local clay is suitable, Or you can Start calling around to pottery shops and find out where the get their
Clays, You will be looking for a "Fire Clay'' a good name brand here would be Lincoln 60 !
This is a link to a site I often send people to for more information ! see below :
http://www.traditionaloven.com/articles/101/what-is-fire-clay-and-where-to-get-it
For a 1st time build -which
should be started and finished out of doors before dragging the whole thing inside your house- there are several economies worth considering
2nd link:
http://www.traditionaloven.com/articles/95/old-red-clay-solids-as-firebrick-alternative
This is where I recommend going to Rocketstoves.com to download a PDF Copy of the brand new 3rd Edition of ''
Rocket Mass Heaters" . This is ''The Book " and will save
you Time, effort, money, and frustration by saving you from many of the more common pitfalls and mistakes . Don't worry about the little bit of math, its all 3rd or 4th
grade stuff and will help you keep your Ratios and your Cross-sectional Areas CSAs uniform throughout your build .
A quick word of warning Metals should never be used in the burn tunnel or heat riser except a sacrificial forms to be burned out during 1st operation, And take anything
you see on You-tube with a large grain of salt. There is a huge boatload of steaming stinking crap Build videos found there - most are a waste of materials and some are
deadly/dangerous !
I hope that this was timely and helpful. For the Good of the Crafts ! Big AL