pe·tun·tze or pe·tun·tse 
(pə-tntsĕ)
(pə-tntsĕ)n.
A variety of feldspar sometimes mixed with kaolin and used in Chinese porcelain.
[Mandarin bái dūnzi : bái, white; see PEKOE + dūnzi, block of stone (dūn, mound, block from Middle Chinese tun, mound, block + Mandarin -zi, noun-formative suffix; see GYOZA).]