gallet

/ˈɡælɪt/
noun
  1. A small chip or splinter of stone, used in masonry or roofing.
    • He collected a pile of gallets from the quarry for the repair work.
    • Roofers often use a gallet to fill small cracks in slate tiles.
    • The mason inserted a gallet into the gap to secure the stone.
Synonyms
What does "gallet" mean? | whatsthatwordmean | whatsthatwordmean