Ntugharị mgbanwe metal na-adabakarị maka ala ciment siri ike, ma ọ bụ ala ụlọ ọrụ nwere ike Mohs dị n'elu 6, nke nwere ike wepu ncha nke ọma site na ichicha igwe, iji gbanwee nke ọma na ọrụ polishing ma mee ka ala gị na-enwu gbaa ma dị nro.