FeSiO3 (ferrosilite) 
Original form Day (1981)
Compiled by H. R. Wakeford 2013
Citation for use this data: Wakeford & Sing (2015) 

wavelength		n			k
8.218	1.5512061	0.05519511
8.94818	1.4363191	0.109983884
9.9078	1.3052595	0.21380487
10.500	1.2719934	0.45549852
10.8646	1.4574625	0.7294559
11.6518	1.7637378	0.6153544
12.941	1.9079088	0.44424278
14.442	1.8014872	0.33792955
17.0379	1.6946592	0.43347466
20.2798	1.7254872	0.6664319
23.1119	1.9024097	0.9482317
26.0496	2.2169878	0.97976404
30.7603	2.450541	0.88183504
33.338	2.4743936	0.8246624