Yes, shard is in the scrabble dictionary

Shard Definition

noun

A fragment of a brittle substance, as of glass or metal.

A piece of broken pottery, especially one found in an archaeological dig; a potsherd.

A small piece or part: "shards of intense emotional relationships that once existed” ( Maggie Scarf).

Zoology A tough sheath or covering, such as a shell, scale, or plate.

Zoology The elytron or outer wing covering of a beetle.