FT-Raman analyses were performed using a near infrared
excitation at 1064 nm provided by an Nd-YAG laser diode coupled
to a Bruker RFS 100/S spectrometer based on a Michelson-type
interferometer, and equipped with a liquid nitrogen-cooled
Ge detector. The reference materials were recorded using a
macroscopic interface equipped with a 90 collecting mirror
allowing the objects to be placed on ahorizontal surface. The
laser nominal power was of 500 mW ( 400 mW at the sample ) and
the spot size about 100 mm. For the archeological samples, a
microscope interface was used with a 40x objective, allowinga
spot size of 30 mm approximately, and a power at the sample of
250 mW (maximum nominal power of 500 mW).