2. Emerald Emerald, known as the king of emeralds, is a very precious gem (May Birthstone) and one of the four precious gems (red, blue, emerald and diamond) recognized by the international jewelry industry. Emerald is one of the oldest gemstone varieties and was used as jewelry in ancient Egypt.
The most expensive of the four kinds of precious stones is diamond. First of all, diamond is the most expensive gem, and its price is higher than other gems. The price of a diamond depends on its size, purity and color. The luster and durability of diamonds are also a major feature. It can last for a long time and is the most popular gem.
4. However, in business, the traditional gems are diamonds, rubies, sapphires, emeralds and gold emeralds, commonly known as five treasures.
5. The most expensive gem in the world is "Golden Lotus with Blood Gallbladder", which is regarded as a sacred object. Blood-gall agate is the most expensive and perfect stone in the world, that is, "blood-gall golden lotus", which is a legend that nature and human beings cannot break through, such as "fish in fish", "gall in stone" and "blood in gall".
6. Diamond, commonly known as "Jin Gangzuan", is a mineral made of carbon, which is an allotrope of carbon. Diamonds are the hardest substances in nature, and they are widely used.