A waste fraction produced in the ore processing contains a large
amount of black mineral, arfvedsonite. The fine, Si-containing,
grains have a wide range of sizes making them suitable as a
substitute for sand in brick production. The relative dark colour
make the bricks darker than usual. They have a normal brick colour
at the very low temperature of 850 deg C and a dark colour at 1025
deg C. The bricks consisted of 30% mine waste fraction and 70% red
burning clay from Denmark.
The strength of the bricks was extremely high. The brick burned
at 850 deg C had a strength 4 times stronger than normal bricks
burned at 1025 deg C. When burned at the same temperature, 1025 deg
C, the strength was 5 times higher.
Figure: Sample brick burned at temperatures from 850 to
1025 deg C (from right to left).
Contact: Andreas Peter Vestbø, firstname.lastname@example.org, +45 7220