Fe2SiO4 (Fayalite) 
Original form Day (1981)
Compiled by H. R. Wakeford 2013
Citation for use this data: Wakeford & Sing (2015) 

wavelength		n			k
8.25294	1.7290225	-0.001408661
8.98569	1.7031654	-0.011201561
9.79624	1.6369854	0.07636566
10.5390	1.6358206	0.17237128
11.5846	1.8365954	0.26039904
11.9800	1.8846524	0.30842894
13.1396	1.8025979	0.21036449
15.2138	1.663452	0.12798494
17.4345	1.6216663	0.19134757
20.3475	1.6769427	0.37570602
23.3801	1.8133795	0.5443254
27.1070	2.0711915	0.6807894
29.9746	2.240434	0.6394371
33.142	2.3288682	0.5821832