Mend your very first piece.
Mend 5 pieces.
Mend 10 pieces.
Mend 25 pieces.
Mend 50 pieces.
Mend 100 pieces.
Mend 250 pieces.
Mend 500 pieces.
Mend 1,000 pieces.
Mend 5,000 pieces.
Mend 10,000 pieces.
Complete a rare golden piece.
Mend one of every kind.
Finish a piece you'd left unfinished.
Complete 7 daily pieces.