1.How does glass classify?
According to the composition,it usually be classified several kinds of glass as follow:
(1)Soda-lime glass: Soda-lime glass is the most common glass, the composition of it is very complex, it mainly include SiO2 (about 72%), Na2O (about 15%), CaO(about 9%), besides, there are little Al2O3, MgO, K2O etc. It usually include many impurity, such as ferrum, so the common glass looks light green. it has widely apply to our daily life and construction due to the cheap cost.
(2)Potassic glass: Soda-lime glass turn to be potassic glass when the K2O instead of Na2O. the rigidity and luster are well, usually be used as chemical equipment and luxury glassware .
(3)Crystal glass: It will turn to be crystal glass when we add about 24% PbO to soda-lime glass. the density of the crystal is high, so it is weight. the rigidity and refrangibility are well, it is used as luxury glassware, ornament and craft.
(4)Silica glass: It's make up of SiO2 which is pure, it's heat-resistant, also has good optic and steady chemical character. it is used as optic equipment and chemical equipment. There are many other kinds of glass, such as broax glass etc.
2.How to distinguish natural crystal and glassware?
It's easy to confuse natural crystal and glassware when they are no color and transparent, but we can differentiate them from below aspect:
(1)Color: the color of crystal is dazzling while there is a little cyan and yellow among the white
glassware, and the brightness of the glassware is lacking.
(2)Rigidity: the brightness of the crystal is 7 while the glassware is about 5.5 .
(3)Impurity: As crystal is natural article, so there would some lacking phenomena while glassware is perfect, as it's manual craft .
3. There are three kinds of process craft:
There are integrated process,usual temperature process and high temperature process:
(1)Integrated process: Made by no less than one process. Including the cool and heat process at the same time.
(2)Usual temperature process: Enchase process; Chemic corrade;sculpture by special tools; sandblast;engraved by laser;incise sculpt;stick sculpt;tridimensional statuary;colorful painting; interlayer.
(3)High temperature process: Blown; Pressing; Cast;agglomeration; Fusing;Enamel; Sagging;Slumping.
