1. The brighter the tourmaline color, the better, not too dark or too light. Among the single color, the bright color tourmalines such as red, rose, green and sky blue are the best, pink and yellow are the second, and colorless is the second. The more single crystals, the better, such as two-color tourmaline, three-color tourmaline and so on.
2, impurities and ice cracks as little as possible, but can not be pursued too perfect. There is no crack in the tourmaline. It is very difficult to ask for a little impurity and ice cracks. The perfect tourmaline and gem-quality tourmaline, but it costs a thousand dollars and 1 carat.
3, some of the tourmaline crystals have a lot of needle-like inclusions, cut into the plain surface more common cat eye effect, mostly green color of the tourmaline. The value of cat's eye effect in tourmaline will increase, but the key to evaluation is the vividness of color, high transparency and block size. There is also a color change effect, and the obvious change of the tourmaline is rare and expensive, and becomes the target of collectors.
4, tourmaline requires crystal clear, the more transparent the better the quality, the higher the transparent value.
Tourmaline knowledge: At present, the price of Paraiba is the highest in the tourmaline. This special neon, blue and green gemstone was first discovered in Sao Josede Batalha, a small village in Paraiba, Brazil in 1989. It is not easy to excavate and the crystal is not large. In recent years, the mining rights have been unclear, disputes have continued, and prices have remained high.
There are many different types and brands of sticker labels on the market, but do you know the classification and use of each different sticker labels? By understanding the label classification and use of self-adhesive can let you better choose a self-adhesive label suitable for their own use. The label classification and use of self-adhesive are as follows:
Mirror coated paper
This kind of sticker labels are advanced multi-color product labels. Usually used in medicine, food, electrical appliances, cultural articles and other items of information label.
Matte paper, offset paper
This kind of self-adhesive label is mostly used for label paper. Usually applied to high-speed laser printing, inkjet printing information labels or bar code labels.
Fragile stickers
The main function is anti-counterfeiting and warranty, this kind of adhesive label after tearing can not be used again. It is usually used for the anti-counterfeiting of electrical appliances, medicines and other commodities.
Polyethylene label
Observed the appearance of the fabric is transparent and bright, the color is milky white.
Thermal paper
Usually in the commodity price above easy to see, more widely used.
PVC shrink film
A trademark used for batteries of all types of electrical appliances and machines.
Coated paper
Apply to multi-color product labels. It is usually applied to the information label of food, medicine and electric appliance.
Laser film
Belongs to the high-grade information label paper, is mostly used for cultural supplies, high-grade decorations and other multi-color product labels.
Aluminum foil
This kind of sticker label is also used for multi-color product labels. It is usually used in the high-grade information labeling of medicine, food and cultural articles.
polypropylene
The surface of this kind of sticker is transparent, sub-silver, sub-gold, milky white, matte milky white, etc. The performance is water, oil, chemical and other important performance of the product label, daily used in the shower supplies, electrical appliances, machinery and other products information label.
Heat transfer paper
Performance to resist high temperature environment. It is commonly used in products such as microwave ovens.
Can remove glue
Fabrics are usually coated paper, mirror paper polyethylene, polypropylene and so on. Because this kind of sticker labels tear off without leaving a trace, usually applied to tableware, fruit and other labels.
Chemical paper
Because this kind of sticker has strong resistance to water and oil, it is usually used for information labels of high-grade products and environmental protection products.
The High Quality,Self Adhesive Labels Sticker,BOPP/PP/NTC/PE or Customized
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