measured	value	unit
[SiO₂]	50.0	%
[TiO₂]	0.19	%
[Al₂O₃]	31.6	%
[Cr₂O₃]	0.91	%
[FeO^T]	0.8	%
[MnO]	0.14	%
[MgO]	0.78	%
[Na₂O]	0.37	%
[K₂O]	10.6	%

tables:

Table 2. Chemical compositions of mica. With the exception of boron, abundances of elements are normalized to a total of 100cg/g of Ota, Tsutomu (2019) Tourmaline in a Mesoarchean pelagic hydrothermal system: Implications for the habitat of early life, Precambrian Research, 334. more