Kaolinite PL measurement, 77K, Bakhtin 1985

Reference	Bakhtin A. I. The Rock-forming Silicates: Optical Spectra, Crystal Chemistry, Colour and their Genetic Origins. - Kazan: Kazan State University Publ. house. - 1985. - 192 p.
Material	Kaolinite [ Al₂Si₂O₅(OH)₄ ] Powder white kaolinite and calcite in a blue-grey Keokuk geode, from St. Francisville, Clark Co., Missouri, USA © Photo by John Krygier (http://www.mindat.org/user-13767.html#0), Public Domain
Specimen temperature	77K
Technique	Photoluminescence (PL)
Lines	Unspecified 500 nm, 520 nm, 540 nm, 580 nm

Nominal composition of Kaolinite [ Al₂Si₂O₅(OH)₄ ].
Element	Atoms	At%	Wt%
Al	2	11.8	20.9
Si	2	11.8	21.8
O	9	52.9	55.8
H	4	23.5	1.56