The selected samples were two pieces taken from classical commercial
glass PLANILUXSGG and colored in red or yellow. One glass without
treatment is used as a reference (REF). The theoretical composition
of this glass was 71.18% SiO2 0.46% Al2O3 12.69% Na2O 9.7% CaO
5.58% MgO. The applied enameling consists in red ochre mixed with
silver sulfate for getting yellow glass. Red ochre mixed with copper
sulfate gives red glass. After depositing the colouring mixtures on
the “float” face [15], these glasses were annealed at a temperature
up to the glass transition temperature (Tg) at T>660 °C during one
hour and fourty minutes. This allowed the decomposition of sulphate
and metallic ions and the ionic exchange occurs between sodium
initially contained in the glass and silver or copper ions onto the
surface of each sample. This also enables their precipitation in NPs
during cooling. The result is shown in pictures in Fig. 1.
A significant part of each sample was cut for the UV/Visible, Infrared
and XRD measurements. A piece of each sample was cut, embedded in
resin and polished on the cross-section to obtain the concentration
profiles by SEM. For TEM measurement, a piece of the samples was
prepared in the following way: a powder was obtained and diluted in
ethanol. The suspension was agitated by ultrasound for 5 minutes. A
drop was collected on a carbon coated copper grid for the observations.