Menu English Ukrainian russian Home

Free technical library for hobbyists and professionals Free technical library


BIG ENCYCLOPEDIA FOR CHILDREN AND ADULTS
Free library / Directory / Big encyclopedia for children and adults

When were gems discovered? Detailed answer

Big encyclopedia for children and adults

Directory / Big encyclopedia. Questions for quiz and self-education

Comments on the article Comments on the article

Did you know?

When were gems discovered?

No one knows when gemstones were first discovered, but man has admired them since ancient times. For thousands of years, jewelry has been worn to ward off spirits and disease. Even today, some people believe in the special power of stones.

The first mention of precious stones we find in the Bible. In the 28th chapter of the book of the Old Testament, it speaks of a body plate worn by a high church minister, Aaron. The plate was decorated with 12 precious stones. The ancient Egyptians used gemstones in ornaments and jewelry. They were skilled in the art of working gemstones, and their designs on stones have survived to this day.

The Egyptians wore amulets known as scarabs. These were precious stones cut in the shape of the sacred Egyptian beetle. It was believed that the one who wears scarabs is protected by good spirits. In ancient times, different gemstones differed in color. The name "ruby" was given to all red gemstones. All green stones were called emerald, and blue - sapphire.

Later it turned out that some gems were harder and more durable than others. It became obvious that the value of a stone depends not only on color, brightness, rarity, but also on its hardness. For example, a diamond is considered today the most precious, because in addition to its magnificence, it also has the greatest hardness among all stones. Many stones are called precious. But in reality, this name refers only to the four most valuable stones - diamond, ruby, emerald and sapphire.

Author: Likum A.

 Random interesting fact from the Great Encyclopedia:

Who discovered Alaska?

When white people appeared in Alaska, they discovered that Eskimos, Aleuts and Indians live here. Alaska is one of the largest territories in the world ever discovered and developed by a white man. At the beginning of the XNUMXth century, Russian sailors were moving through Siberia to the Pacific Ocean.

In 1728, Vitus Bering, a Dane in the service of the Russian government, sailed east of Kamchatka. He sailed along the island of St. Lawrence, but did not reach mainland Alaska. In 1741, Bering led a second expedition on two small ships. He commanded one of these ships, the St. Peter, and the St. Paul was commanded by Alexei Chirikov. The ships were scattered by the storm, but they both reached Alaska.

For the next two centuries, Russian hunters hunted furs in the waters of Alaska. They founded many settlements, and in many places there are still quaint churches built by the Aleuts and Indians under the leadership of Russian missionaries. Subsequently, the coast of Alaska was mastered by the sailors of Spain, France and Great Britain. But it was the Russians who used Alaska as a source of furs, which they supplied in huge quantities to European capitals. Then the number of fur animals began to decrease, and by the 1820s, the Russians began to leave the coast of Alaska.

Russian Tsar Alexander II was not too interested in Alaska. Lincoln-era Secretary of State William H. Seward persuaded his government to buy Alaska from the Russians, and in 1867 Alaska was sold to the United States for $7, less than two cents an acre! Today Alaska is not just the forty-ninth state of the USA, the value of this territory can hardly be measured in dollars!

 Test your knowledge! Did you know...

▪ When was the first sound recording made?

▪ What is a camera obscura?

▪ What animals have cubic feces?

See other articles Section Big encyclopedia. Questions for quiz and self-education.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Machine for thinning flowers in gardens 02.05.2024

In modern agriculture, technological progress is developing aimed at increasing the efficiency of plant care processes. The innovative Florix flower thinning machine was presented in Italy, designed to optimize the harvesting stage. This tool is equipped with mobile arms, allowing it to be easily adapted to the needs of the garden. The operator can adjust the speed of the thin wires by controlling them from the tractor cab using a joystick. This approach significantly increases the efficiency of the flower thinning process, providing the possibility of individual adjustment to the specific conditions of the garden, as well as the variety and type of fruit grown in it. After testing the Florix machine for two years on various types of fruit, the results were very encouraging. Farmers such as Filiberto Montanari, who has used a Florix machine for several years, have reported a significant reduction in the time and labor required to thin flowers. ... >>

Advanced Infrared Microscope 02.05.2024

Microscopes play an important role in scientific research, allowing scientists to delve into structures and processes invisible to the eye. However, various microscopy methods have their limitations, and among them was the limitation of resolution when using the infrared range. But the latest achievements of Japanese researchers from the University of Tokyo open up new prospects for studying the microworld. Scientists from the University of Tokyo have unveiled a new microscope that will revolutionize the capabilities of infrared microscopy. This advanced instrument allows you to see the internal structures of living bacteria with amazing clarity on the nanometer scale. Typically, mid-infrared microscopes are limited by low resolution, but the latest development from Japanese researchers overcomes these limitations. According to scientists, the developed microscope allows creating images with a resolution of up to 120 nanometers, which is 30 times higher than the resolution of traditional microscopes. ... >>

Air trap for insects 01.05.2024

Agriculture is one of the key sectors of the economy, and pest control is an integral part of this process. A team of scientists from the Indian Council of Agricultural Research-Central Potato Research Institute (ICAR-CPRI), Shimla, has come up with an innovative solution to this problem - a wind-powered insect air trap. This device addresses the shortcomings of traditional pest control methods by providing real-time insect population data. The trap is powered entirely by wind energy, making it an environmentally friendly solution that requires no power. Its unique design allows monitoring of both harmful and beneficial insects, providing a complete overview of the population in any agricultural area. “By assessing target pests at the right time, we can take necessary measures to control both pests and diseases,” says Kapil ... >>

Random news from the Archive

An insulating material that is a conductor at its edges 14.06.2018

Physicists at the University of Zurich have discovered a material that belongs to a new class of higher-order topological insulators. The faces of crystalline solids made of these materials conduct electrical current with almost no resistance, while the rest of the material remains an insulator. Such unique properties of new materials can be very useful for creating new types of electronic devices and, of course, for creating quantum computing systems.

Topology, a science that is part of materials science, deals with the study of the properties of solid particles and bodies protected from deformations and the effects of various external factors. One of the directions of this science is the study of topological insulators, crystalline materials that conduct electric current only in the surface layer. At the same time, due to some physical effects, conductive surfaces cannot be transferred to an insulating state.

Theoretical calculations carried out by physicists have shown that the properties of higher-order topological insulators must be extremely stable. In other words, the electrical conductivity of the crystal faces should not be affected by impurities and other disturbances of the crystal lattice. In addition, the crystal faces do not need additional processing or any initiation to obtain conductive properties. And even if the crystal suddenly breaks, the electric current will still continue to flow through it along the newly formed faces.

These studies are now mostly in the theoretical field. But researchers have already proposed one material that could be a higher-order topological insulator, tin telluride. "Soon we will find other materials with similar properties" - says Professor Titus Neupert (Titus Neupert), - "The edges of these materials will work as a kind of "highway" for electrons, i.e. they can be used as moreover, topological insulators can be combined with magnetic, semiconductor and superconducting materials, which will allow them to be used to create quantum computers."

Other interesting news:

▪ Seals get the flu too

▪ Smart alarm clock EzLarm

▪ Human warmth - a threat to computer security

▪ Airless tires of the future from Michelin

▪ Seagate Video 2.5 HDDs for continuous use

News feed of science and technology, new electronics

 

Interesting materials of the Free Technical Library:

▪ site section Power supply. Article selection

▪ Jeans article. History of invention and production

▪ article In which city is the hotel where the homeless sleep? Detailed answer

▪ Rose article. Legends, cultivation, methods of application

▪ article Suppressor of impulses of a bounce of contacts - a shaper of impulses. Encyclopedia of radio electronics and electrical engineering

▪ article Electrolysis and electroplating installations. Magnesium electrolysis plants. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

Name:


Email (optional):


A comment:





All languages ​​of this page

Home page | Library | Articles | Website map | Site Reviews

www.diagram.com.ua

www.diagram.com.ua
2000-2024