Castaic FireBrick? Is it ok?

[breakn]

Im using the same post so as not to muddy the site. I was curious if anyone had used this brick and was satisfied with it. I was unable to get an answer on the silica and aluminum content percentage.
I bought some fire brick locally (Tucson) and it is the correct size 2.5x4.5x9, But it is red. So I wasnt sure if this is the right stuff. So i called the company castaic brick or pacific clay products. I inquired what grade it was, but they dont make different grades. They said its firebrick and will work for my oven. I had them email an msds sheet and here is what it says.
A. PRODUCT IDENTIFICATION;
FIRED CLAY PRODUCTS CONTAINING NO ADDITIVES:Firebacks (Extruded).
Products Components
<P> ------------------- CAS - % by Wt - ACGIH TIV - CSHA PEL
<P>1. Aluminum Silicates: Var, 50-70, 10 mg/m³, 15 mg/m³
<P>2. Mineral Compounds of Var, 7-9, 10-15 mg/m³, 10 mg/m³
<P> Iron, Calcium
<P> Magnesium:


So I am confused as too what the actuall alumina content is.

So if any one can comment on it, i would appreciate it. maybe someone has used castaic or knows something about it. I want to be sure, because there is no turning back once I start. Thanks

[dmun]

I don't know about this specific product, but there is red firebrick. Well, sort of red. And it tends to fade.

[Tscarborough]

It should be fine. I have both red and buff firebrick and the specs are the same for both.

[breakn]

I just dont want it to end up being insulating fire brick that wont hold the heat.

[Tscarborough]

As a rule, insulating fire brick will be white and light.