TY  - JOUR 
T1  - Infrared and chemical characterization of natural amethysts and prasiolites colored by irradiation
JO  - Materials Research
A1  - Lameiras, Fernando Soares
A1  - Nunes, Eduardo Henrique Martins
A1  - Vasconcelos, Wander Luiz
SN  - 1516-1439
UL  - 10.1590/S1516-14392009000300011
VL  - 12 
Y1  - 2009
PB  - Brasil 
ER  -