fireboard
/ˈfʌɪəbɔːd/noun
1A board or screen used to cover a fireplace; a chimney board. In early use also: a fireguard.
2A type of board capable of withstanding heat; a fireproof or fire-resistant board.
3A piece of wood on which a fire drill is used to start a fire by friction.
4A ledge or shelf above a fireplace; a mantelpiece.
Origin
Mid 18th century. From fire + board.