Different types of fire bricks. What can happen???

[Chris inPA]

That's what I was hoping to hear

[UtahBeehiver]

Should not be an issue.

[Chris inPA]

I was told by the person that I bought my fire bricks off of that they were all medium duty fire bricks.

As I'm saw cutting these they appear to be very different. The "white" bricks cut easier than the other 2 colors and I think that they weigh slightly less. (I didn't put them on a scale, but they don't feel as heavy).

There is less matrix to the lighter color brick also.

What issue would result if I intermittently mixed these?