Colored gems's shopping tips, colored gems's classification
Colored gems, also known as colored gems, is not a kind of gem, but the floorboard of all colored gems in the gem family. Colored gems is divided into three grades, and the advanced colored gems is ruby, sapphire, emerald, cat's eye and alexandrite. There are many kinds of mid-range colored gems, such as tourmaline, garnet, tanzanite and opal. Among them, tourmaline and garnet are no less than emeralds and rubies. There are many kinds of low-level colored gems, such as prehnite and Moonstone. Low-grade gems have no collection value.
Determinants of value
Natural: Most domestic gemstones are heat treated, and the stones after heat treatment are bright in color. When buying gems, you'd better choose pure natural ones. Pure natural colored gems has higher price and collection value than heat treatment.
Weight: The price of precious stones is different from other things. For example, radish is two yuan a catty and four yuan a catty. If a carat gem costs 2000 yuan, the price of two carats is not 4000 yuan, but several times. Generally speaking, colored gems whose weight exceeds these carats is worth collecting: rubies over 2 carats, sapphires over 5 carats, emeralds over 3 carats, metamorphic rocks over 3 carats and cat's eyes over 5 carats. For example, blue gemstones can be divided into different grades, such as 5, 10, 15, 20, 25, 30 carats, etc. It is better to choose 10.0438+0 Crabbie 9.99 carats, because the higher the carat, the higher the gem value.
Origin: colored gems pays attention to the origin, and the origin itself is a brand. Ruby of the same weight and grade made in Myanmar will be much more expensive than that made in Thailand. Generally speaking, the best origin of rubies is in Myanmar, emeralds are in Colombia, sapphires are in Myanmar, Sri Lanka and India, and cat eyes are in Sri Lanka. Many gems have cat's eye effect, but they are not called cat's eye gems. Only Sri Lankan emeralds and Alexander metamorphic rocks are recognized as cat's eye gems in the world. The price difference between a real cat's eye and a gem with cat's eye effect is much different. Cat eyes. What else is there? Live cat's eye? And then what? A dead cat's eye and a living cat's eye are like cat's eyes, opening and closing. If the dead cat's eye doesn't move, the two prices are also far apart. The best color of cat's eye is honey, which is the color of honey and the highest price.
Color: two emeralds of the same size, if one is dark and the other is light, the dark one is better and the price is higher; Sapphire and Yache Blue are the authentic colors of sapphires, which are also recognized by the world, and are more valuable for collection and investment.
Certificate: At present, the internationally accepted gem certificate is issued by GRS laboratory, and the most authoritative one in China is the certificate issued by the National Jewelry and Jade Quality Supervision and Inspection Center. It is more convenient to choose certified gems, especially when buying for investment purposes, so as to realize them in the future.
Light: Don't look at colored gems in strong light, look at it in weak light. The weaker the light, the better. In weak light, gems will glow. If you can see the fire color, this kind of gem is a good gem with good grindability and low dispersion value.