Anorthite CL/OM measurement, Telfer & Walker 1978

Reference	Telfer D. J. & Walker G. (1978). Ligand field bands of Mn2+ and Fe3+ luminescence centres and their site occupancy in plagioclase feldspars. Modern Geology, 6(4), 199-210.
Material	Anorthite [ CaAl₂Si₂O₈ ] Anorthite specimen from the type locality at Somma-Vesuvius Complex, Naples Province, Campania, Italy. Size: 6.9 x 4.1 x 3.8 cm 2010 Rob Lavinsky, iRocks.com, CC-BY-SA-3.0
Specimen temperature	Ambient
Analysis technique	Cathodoluminescence (CL), using an optical microscope
Lines	Mn²⁺ 30960 cm-1, 29540 cm-1, 28420 cm-1, 24830 cm-1, 24000 cm-1, 21010 cm-1, 31070 cm-1, 29600 cm-1, 24770 cm-1, 23870 cm-1, 21430 cm-1, 31150 cm-1, 29420 cm-1, 28170 cm-1, 24750 cm-1, 23750 cm-1, 20550 cm-1

Nominal composition of Anorthite [ CaAl₂Si₂O₈ ].
Element	Atoms	At%	Wt%
Ca	1	7.69	14.4
Al	2	15.4	19.4
Si	2	15.4	20.2
O	8	61.5	46
Total	13	100	100