Do I have the right bricks?

[Dolf]

Hi All
I am a newby but have been lurking the forum for a while and have studies the plans (thanks for posting for free!).
My concern is if I have the right bricks. I got a stack for free. 220x110x60. They came out of a Pilkingtons glass cooling area when the plant was refurbished in 1978. So these bricks bave been lying in the back of the garden for years hence the old/soil look on some. As you can see they have ECLIPSE and VR writen on them. They weigh 3.7kg each but when submerged they hardly pick up any weight. They are difficult to cut. I add a pic to show colour and “texture”. So Question 1 is if I can use them (hope you say yes!)
Question 2 deals with the square brick also in a pic with a VR3 rating. These were used in another area of the plant but the guy who gave them to me cant remember where. I have just enough of them to make a floor if you guys ok them. They weigh the same as the others pro rata
Thanks for any help
Dolf

PS. I tried this post yesterday as well but do not see it - hope I did not create a duplicate

[wemme]

well for density unless i balls up the calcs your looking at about 688 bricks per cubic meter at 3.7 kgs end up being about 2.5 tonnes/m3 so the density is right.

insulating bricks are around 600-700kg per m3 and heat storing are around or over 2000kg/m3
still will be interesting what other have to say about the matter

[dmun]

They sure look like firebricks to me. The flat tile I'm not so sure about, but it could be refractory tile.

[ThisOldGarageNJ]

Dolf,
Try testing them, build a fire in the backyard, put a few of the 2 differrent bricks in,, burn for a while,, see if they hold the heat for a few hours after the fire goes out, make sure they dont split or crack....etc...

Cheers
Mark

[Dolf]

Thanks gents. I'll try the quick-pack test and report back.