I really hope they are not kiln bricks! then can be worthless,, My fathers friend trusted some of those fake au bars (made in philex mines) last 1980s,,they are just lying on his toolbox,, i stole and sold some few bars at metal scrap buyer for 25 pesos per kilo,,as an elementary student,350 pesos makes me the riches man in the school campus...Now,,I wonder if those bars i sold are those circulating around this days? he-he! i dont like to admit that im part of this modern scam!!! should that scrap metal buyer has to do with it??? nobody knows....