A mantle piece is a decorative shelf that is typically placed above a fireplace. The term can also refer to the entire structure, including the mantel shelf and the surrounding wall. The crossword solutions for the term mantle piece are MAGMA (5 letters), URN (3 letters), and EWER (4 letters). MAGMA is molten rock beneath the surface of the Earth, an URN is a container used to store ashes, and an EWER is a pitcher-like vessel used for pouring liquids.