The concept of gem (in a broad sense): any material that can be used as jewelry and handicrafts after pondering and carving. It includes natural gemstones and artificial products.
Natural gemstone
Natural gemstones refer to substances produced in nature, which are beautiful, durable and rare, have technological value and can be processed into decorations. Natural gemstones are divided into gemstones (in a narrow sense) and jade.
Gem (narrow sense): The concept of narrow sense gem refers to the mineral single crystal gem produced in nature. This is the most common kind of gem. The single crystal mentioned here means that the whole gem consists of a single crystal, which looks crystal clear. Such as diamonds, rubies and crystals.
Jade: According to our traditional custom, jade refers to the polycrystalline mineral aggregate gem produced in nature. In other words, it is composed of multiple crystals. The structure of this polycrystalline aggregate is sometimes invisible to the naked eye, but it is easy to observe under the microscope. From the appearance, jadeite is mostly translucent to opaque. There are different kinds of jade according to different minerals. Such as jadeite and nephrite.
Natural gemstones are divided into inorganic gemstones and organic gemstones according to their composition and formation mode:
Inorganic gems are formed by natural geological processes, and the composition is mainly inorganic. Most precious stones fall into this category, such as diamonds and jadeite mentioned above.
Organic gemstones are gems produced by natural organisms and partially or completely composed of organic substances. Such as pearls and ivory.
Naming rules of natural gemstones: National standards stipulate that natural gemstones can be named directly with the name of natural gemstones, without adding the word "natural". Such as diamonds, rubies and sapphires. In other words, if there is no modifier before the name of a gem, it must be natural. Generally speaking, the place of origin does not participate in naming, such as South African diamonds and Burmese rubies.
imitation jewel
Due to the limited natural resources, there are fewer and fewer natural gems, which can't meet people's demand for jewelry. At the same time, with the improvement of science and technology, people use artificial methods to make gems in laboratories or factories. Then came the man-made product.
Materials that are wholly or partially produced or manufactured by people and used as jewelry and handicrafts are called artificial products. It includes synthetic gems and artificial gem.
Synthetic gemstone: a crystal or amorphous substance that is completely or partially artificially made and has a known natural counterpart. Its physical properties, chemical composition and crystal structure are basically the same as the corresponding natural jewelry and jade. If there are rubies in nature, people will imitate the chemical composition and structure of natural rubies to make rubies artificially. This kind of ruby is called artificial ruby.
Artificial gem: Artificial crystal or amorphous body with no known counterpart in nature. Such as synthetic yttrium aluminum garnet. This is a kind of crystal that can only be made in the laboratory. There is no natural yttrium aluminum garnet in nature. So it is a kind of artificial gem.
Naming rules of artificial products: National standards have strict regulations on naming methods of artificial products to distinguish them from natural gems. For synthetic gemstones, the word "synthetic" must be added before the corresponding natural gemstone. Such as synthetic rubies and synthetic diamonds. For artificial gem, it is generally necessary to add the word "artificial" before the name of the material, such as "artificial yttrium aluminum garnet".
As the saying goes, "Gold is valuable, but precious stones are priceless". Are gems really priceless? No, gems are very valuable. At present, the pricing of diamonds is more scientific and strict. The fluctuation of diamond price is directly influenced by the international market, especially controlled by De Beers Diamond Company, the largest diamond company in the world. The value of precious stones is not constant. A gem is often influenced by many factors, such as color, size, texture, transparency, polishing and so on, and the difference in value can reach several times to hundreds of times. In addition, all kinds of gems are often influenced by various factors such as color and size, especially with the changes of times, fashion, national traditions and hobbies, the output of gems and the discovery of high-quality new varieties, and the value of gems fluctuates. It is pointed out that the rarity and fashion of gems have the greatest influence on the value of gems. The value of a gem mainly depends on its beauty, rarity and durability. People usually call diamonds, rubies, sapphires, emeralds and emeralds precious or high-grade gems, while garnet, amethyst and olivine are low-grade gems. The prices of high-grade and low-grade gems are quite different. For example, the value of L-carat high-quality diamonds exceeds 1 1,000 US dollars, while the value of 1 carat high-quality amethyst is only 1 ~ 2 US dollars. The value of precious stones also depends on ethnic groups and habits, such as jadeite, which has been loved by people in Asian countries with oriental nationalities for centuries. Westerners don't like jade very much, but they prefer diamonds. Some high-grade gems fluctuate in value with the progress of the times. /kloc-Before the 0/5th century, the precious stones in Shangcarat had the highest value, followed by rubies. /kloc-in the 0/9th century, diamonds took the lead, and then emeralds took the lead. This phenomenon is mainly determined by the law of social and economic development. Some gems are recorded in history and have the status of cultural relics and antiques. Precious as a national treasure, its value is not determined by market conditions, and its value is very expensive. Natural gemstones are also a kind of natural resources. People will use them up. If they are mined indefinitely, the less natural gems are produced, the higher their value will be.