...I believe the insulator ones are lighter & more porous like & the conducting ones are heavier & more dense / solid..........
Hmmmm. I have about 12 firebricks. All the thinner ones bought from 2 different places. One type is the lighter porous one and the other much heavier and dense. It had not occurred to me that I had firebricks that performed differently.
@1buckie - Any thoughts on what would be good applications for one type or the other?
It seems the more porous, lighter ones might be the type with the "insulative property" & might be best used for blocking heat, as in banking coals & keeping an area on the outside a bit cooler...
The "conductive" type, guessing those are the more dense & heavy, might be best for blocking up pizza or right under something you'd want to transmit heat to....
Look back up to the quote by G$......didn't actually see the research, but I think the differences are that way based on this:
![](http://i1223.photobucket.com/albums/dd520/1buckie/BBQ%20%205%201%207%208%20%20%20%202011/KenBBQ5782011020.jpg)
these are 'Turds that were hanging out over the prop-up brick I use against an upright flip-up.....heavy & dense.....
You can see below, I learned my lesson, as the bacon wrapped doughnut is
NOT over the brick.....
![](http://i1223.photobucket.com/albums/dd520/1buckie/BBQ%20%205%201%207%208%20%20%20%202011/KenBBQ5782011037.jpg)
Not absolutely sure, but these newer ones I bought at a decorative stone place I believe are the insulator type.....a little lighter, but not by much........this could be actually the dense heavy stuff, just a newer version of it.....
![](http://i1223.photobucket.com/albums/dd520/1buckie/Sept%208%209%20%202012%20clouds%20pie/Pie%203%20%20PP%20Tacos/Pie3041.jpg)
.....but, it seemed to take awhile to come up to temp & heat the CI pan for a baking...
![](http://i1223.photobucket.com/albums/dd520/1buckie/Sept%208%209%20%202012%20clouds%20pie/Pie%203%20%20PP%20Tacos/Pie3043.jpg)
Best guesses.......
![Grin ;D](https://weberkettleclub.com/forums/Smileys/default/grin.gif)