A form of limestone deposited by mineral springs, especially hot springs. Used in geology and mineralogy.
この地域の温泉では、灰華がよく見られる。
Travertine is often seen in the hot springs of this region.
Compound of 灰 (かい, 'ash') and 華 (か, 'flower'), likely referring to the porous, ash-like appearance and the flower-like formations of travertine deposits. The exact historical derivation is uncertain.