Page 1 of 1

Posted: Mon Mar 07, 2016 4:32 pm
by Nishing
Hello, i am doing a small patio and started removing the top soil from the area and i found lots of bricks with this black granular stuff inbetween them, i would like to know what it is and whether i need to remove it.

Its like black perlite, its easily crushed into powder inbetween my fingers and it leaves black smudges. I thought it must be coal slag but i looked for pictures of coal slag and im not sure if its the same stuff.

Anyone know what it is?

Thanks

Posted: Mon Mar 07, 2016 6:08 pm
by lutonlagerlout
sounds like fly ash,they used to use it as subbase
cant see it so cant say if its any good but there loads buried in my garden
LLL

Posted: Tue Mar 08, 2016 1:05 pm
by Nishing
Yes i think you may be right, there used to be tarmac in the area i guess that would make sense.

Thanks