MnS (natural mineral  alabandite (isometric), rambergite (hexagonal), also in meteroites as brownite) 
Original form Huffman & Wild (1967)
Compiled by H. R. Wakeford 2013
Citation for use this data: Wakeford & Sing (2015) 

wavelength		n			k
0.146581	0.49438587	1.3802475
0.1750042	0.5343623	1.538969
0.1926536	0.5892548	1.6877232
0.207065	0.7033873	2.1137497
0.2247829	0.87197053	2.213072
0.236453	1.0305154	2.237991
0.248161	1.1741973	2.129302
0.259730	1.3079647	1.951299
0.286640	1.4072518	1.3924241
0.326188	1.4422622	0.86822385
0.361639	1.4177849	0.40329897
0.413690	1.2696319	0.101761416
0.459769	1.2005656	0.00312813
0.598939	1.1119353	0.00643299
0.922439	1.0580148	0.00597349
1.725110	1.0386628	0.005531664
3.609400	1.0290309	0.005142857
4.000000	2.614	0.0000001
5.000000	2.605 	0.0000001
6.000000	2.595 	0.0000001
7.000000	2.582 	0.0000001
8.000000	2.570 	0.0000001
9.000000	2.554	0.0000001 
10.000000	2.532 	0.0000001
11.000000	2.508 	0.0000001
12.000000	2.478 	0.0000001
13.000000	2.435	0.0000001