To those who are not that familiar with dZi, the word ChungdZi is the synonym of line dZi. But actually ChungdZi is referred to "secondary level dZi", and it is not line dZi. dZi which is not beautiful enough, not big enough, not decent enough is considered as secondary level dZi, in Tibetan language it is called "ChungdZi", otherwise, it is "dZi". The early stage of the Tibetan dZi strand, it usually put a big line bead in the middle and the two sides are the other eye beads, so it can tell, in the mind of the Tibetans, the big line dZi over 50 mm in size can meet the standard of "dZi", or it might be what "big zee zee" is referred to in the "Book Prefecture First Tortoise".