#tessera  a small square tile of stone or glass used in making mosaics
  supertype:  tile  a flat thin rectangular slab (as of fired clay or rubber or linoleum) used to cover surfaces
  subtype:  tessella  a small tessera
  part of:  mosaic  art consisting of a design made of small pieces of colored stone or glass

No statement uses or specializes tessera; click here to add one.