Specific gravity: 2.46 to 2.5Linear expansion coefficient: 9 ~ 10x10-6 / oc (~ 350oc)Specific heat: 0.2 (0o ~ 50oc)Practical surface tensile strength: 500kgf / cm2Glass call originated in the Tang, referring to the glass material plus lead oxide called in gems. While adding lead oxide when the ratio is defined with the countries habits are different, in general, the proportion of lead oxide more than 24%, transmittance and refractive index of glass are good, but also heavier, softer, very Suitable firing into fine glass art. When the United States and Europe are generally referred to crystal ware, referring to the use of such crystal glass, which is expensive is not an ordinary glass can match. Artificial glass "glass" is glass, but added lead becomes very sparkling crystals have people call it. In terms of pure artistic vision to appreciate, of course, also has a collection value. If the participant Natural crystal glass natural energy or time to grow is vastly different. This is sure to understand. Like Austria or Italy, the high price of crystal cup glass plate bottle, or crystal glass decorations used in a variety of cute little animals, Crystal Lotus Buddhism with glass, crystal chandeliers, almost all glass Imitation Jewelry! There is no magnetic energy. Crystal glass is actually made of glass imitation of natural crystal, which is often heard of lead glass, lead glass is added to increase the refractive index of the glass, but also to make it easier to reduce the hardness pondering; generally sell beautiful crystal glass is leaded glass.
The difference between crystal and glassCrystal and glass looks very similar, but it is two completely different substances. The main difference in the following five areas:
1.different materialsCrystal is a gems of silicon dioxide, while the glass is in a molten state comprising a mixture of silica.
2. the effectiveness of differentGlass only decorative, but in addition to the decorative effect of crystal, as well as the piezoelectric effect, have a special role in health care.
3. different prices
Imitation Jewelry unit price several times higher than even a few times.
4. different physical properties
(1). Crystal is a crystal with high hardness (7 Mohs), while the lower hardness of the glass, (5.5 Mohs), the crystal can be scratches on the glass, not vice versa.
(2). Crystal is a crystal, better thermal conductivity, tongue licking touch has the feeling of cold. The glass is even warm.
(3). Using polarized light microscopy difference, crystal can be opaque, but the glass does not.
We can easily distinguish them based on different physical properties of crystal and glass have.
5. different processing
Glass can be hot cast, low labor and material costs. Crystal is a gemstones manufacturers, can not be reversed after heating to melt, it is not hot-casting method, only with cold, etc. Cutting Method. Material costs and labor, high cost.
Crystal high hardness, easy to wear. Low glass hardness, easy to rub the hair.
Good crystal stability, long-term use does not change color. The glass is easy to turn yellow.
colored glaze and crystal (West Crystal glass) What is the differenceA. in the history books there is a clear distinction between
gems Sutra and there were similar record. In all Buddhist China, the Buddhist Qibao front five is recognized, namely gold, silver, glass, Tridacna agate * * mollusks, the latter two are said to be crystal, said to be amber, glass and so forth, indicating that the glass is recognized Buddhist treasures; glass and crystal and glass different.
B. of different chemical composition
Natural crystal, glass, the main component of glass is silica. Contemporary national authority monograph "Chinese ancient glass research," reads: 92 percent of Ancient Egypt "Fayence" (that is, the ancestor of the West gemstones manufacturers) proportion of silica (not transparent) -99% of the glass Chinese Zhou dynasty , proportion of silica is only slightly greater than 90% (transparent). This 9% difference is the biggest difference between glass and crystal.
C. ingredients Comments
Ancient glass with lapis mother baked the added glass, lapis is a colored crystal material, the main ingredient should be mainly silica, glass collected from the mother is a kind of natural and artificial after refining ancient recipe, you can change the structure and physical properties of the crystal, there are significant differences in the shape, color and transparent degree.
Ming Dynasty jade medicine should be a little different on the mother glass formula, so the Ming Dynasty jade medicine less color change, nor transparent. Glass level really depends on the mother glass raw materials and preparation method, which is secret does not pass the ancient times, precisely because of the presence of the mother glass, only to Chinese healing glass and crystal gemstones manufacturers and even the West "Fayence "With nine percent of the difference in the ingredients. The so-called glass Lucky, security and peace, and the mother glass has a great relationship.