Thorium is silvery and tarnishes black when it is exposed to air, forming thorium dioxide; it is moderately hard, malleable, and has a high melting point.
Thorium mawarna kapérakan miwah pangotor manados selem ri kala keni udara, ngawentuk thorium dioksida; bélék, aluh karupa, miwah ngelah titik léléh sané tegeh.