Rock and Metal

/rɒk/

noun

• the solid mineral material forming part of the surface of the earth and other similar planets, exposed on the surface or underlying the soil.

/ˈmɛt(ə)l/

noun

1. 1.

   a solid material which is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity (e.g. iron, gold, silver, and aluminium, and alloys such as steel).