Haum rau ferrous hlau, non-ferrous hlau, IC nyias seem, coatings, ply-hlau;iav, ceramics, agate, pob zeb muaj nuj nqis, nyias yas seem thiab lwm yam .;hardness kuaj xws li hais tias ntawm qhov tob thiab lub trapezium ntawm carbonized txheej thiab quench hardened txheej.