Homemade Vermiculite fire brick - test furnace melting aluminium with blowtorch -- YouTube || My own fire bricks being tested. Made from by volume: 12 Vermiculite, 4 Building Sand (silica and clay), 2 Cement, 3 Water. Density is 1170Kg/m3 (roughly 60% of a normal brick)...

Homemade Vermiculite fire brick - test furnace melting aluminium with blowtorch -- YouTube || My own fire bricks being tested. Made from by volume: 12 Vermiculite, 4 Building Sand (silica and clay), 2 Cement, 3 Water. Density is 1170Kg/m3 (roughly 60% of a normal brick)...