Cast Iron or Soapstone???

OK, I actually have a question worth answering.

Suppose my bricks started exploding, no pun intended, and I had to replace them.
Can I replace them with soapstone bricks? Would it compromise the functionality
of my Lil' Bo Peep Rainier? My gut says no, but then, it often complains falsely of
hunger when I crash wedding parties.

Probably a question best asked in a seperate thread.. but.. No IMHO your stove would work fine, no harm to the STOVE would come from doing it.. your WALLET may be unhappy. The "firebricks" in the bottom of the Mansfield are soapstone. They run about $30 a "brick" to replace. A 5 pack of firebrick at TSC is about $10..

Probably a question best asked of the manufacturer and why they have them in there. Soapstone and insulating (light) firebrick have different properties - the most basic of which is that soapstone absorbs quite a lot of heat and conducts it over time, whereas insulating firebrick doesn't do either that much.
See here:
http://www.tulikivi.com/en/fireplaces/Soapstone_Properties_of_soapstone
http://www.traditionaloven.com/articles/81/insulating-fire-bricks

See also dense firebricks here which are closer to soapstone in some respects.

Now, I'm not predicting it will cause the stove to disintegrate but clearly you're putting something in that plays a different role. Whether or not that function is integral to the design or not, I don't know.

It may just be that the stovemaker wanted the metal part of the stove to be isolated from the direct thermal shock of flames, which either type of brick might do, and the lighter firebrick is cheaper.

Dakota: YOWZA, that's a heckavuh price difference. You sure the Arabs aren't in on this racket?
I oughta get into it ... hmmm ... lessee ... I gotta figger out how to put more soap in the stone
so I can pad each brick ...

Armoured: As I suspected. Better be safe than sorry. Eventually I'll drop a line to Travis just to see
what he says. Of course, he'll refer me to Jethro, who doesn't even know what soapstone is. At least
Jethro knows fire comes from rubbing two sticks together and not banging two rocks together. If Jethro
isn't busy rubbing sticks, he's busy banging Ellie May, but I suppose that's best left for another thread.