Corrigendum to “Natural mullites: chemical composition, crystal structure, and optical properties” published in Eur. J. Mineral., 31, 353–367, 2019
The universal mineral formula for natural mullites presented here contains a typing error. The mineral formula, given on p. 358 (Sect. 4.1), in the heading of Table 7a (p. 361) and at the end of Sect. 4.2 (p. 363), is stated as MMgMMMO10−x.
However, the indexing of M3+ is erroneous. The parameter w must contain a factor of 2. The correct formula is MMgMMMO10−x.
Consequently, also the formula NayMgzCawAlSiO9.75 given on p. 359 must be stated as NayMgzCawAlSiO9.75.
The citation “Angel and Prewitt (1987)” on p. 357 is incorrect. It is “Angel and Prewitt (1986)”.