practice of 'yobitsugi'

I recently practiced 'yobitsugi' in the workshop.
 It is to repair broken ceramics using a piece from another ceramics.
'yobi' means 'invite' or 'call' ,'tsugi' means 'kintsugi'.

 I had prepared these sake-cups. 
Their size look almost similar, but in fact,their thickness and radius are a bit different.

First, I broke a cup and assembled it together again with lacquer leaving one piece aside.

Then, I cut out a piece from the other cup and put it into the assembled one.

This technique needs a skill to put together a piece which is not really 
the same shape with the lack, 
and also needs a sense of beauty to decide from which ceramics to take the piece to fill the lack.