Bests & Worsts Reviews from Amazon

I purchased these firebricks to use in building a home made smelting oven. Originally, I did not know that there was a difference between "soft insulating fire bricks" and "hard fire bricks". These are "hard" fire bricks. They are meant for high temperature CONSTRUCTION or repair, but NOT as insulation inside an oven or furnace. They are structurally strong, but not very good heat insulators. I ended up buying a bunch of soft insulating fire bricks for my project, but all was not lost since I was able to use these hard bricks as structural pieces (floor, outer wall, supports, etc..) for my oven project. They are strong, nicely made, the dimensions are very exact (they fit together beautifully), they cement together nicely with refractory cement and they withstand lots of heat (being heated bright red doesn't hurt them a bit). As structural fire bricks they are great. But if you need high temperature INSULATION, you need SOFT INSULATING firebricks, not these.