By weight California. Metal worth $250 million per gram is produced in the Ulyanovsk region

Californium

- chemical element, actinide.

Silver $1.1 per 1 gram - 10th place.

No matter how paradoxical it may sound, silver is one of the expensive metals, but at the same time silver is one of the cheap metals. The price of silver per 1 gram does not exceed $1.1. It is very popular among different nations. It has become the favorite substance of many women and the “hero” of mystical fairy tales, as the main weapon against evil spirits. Many peoples claim that silver can heal.

In Babylon, silver was sacred and was a symbol of the Moon. In the Middle Ages, silver was popular among alchemists. Silver was and is used for minting coins.

Artificial elements:

Californium

$6,500,000 per gram

There are several isotopes of californium, with californium-252 having the greatest practical application. Radioactive californium stands apart even among the most expensive metals. This is explained both by its huge price and special properties. The energy released by one gram of californium is comparable to the power of a conventional nuclear reactor.

Several milligrams of the metal are produced annually, and the total amount of Californian produced over all years does not exceed 5 grams. The main application is scientific research in the field of nuclear physics and medicine.

Osmium $41.6 per 1 gram - 6th place.

It received this name because of its unpleasant odor (from the Greek “osme” - smell). Osmium was discovered in 1803 by English chemists Smithson Tennant and William H. Wollaston in the precipitate remaining after dissolving platinum in aqua regia.

Pure osmium has not been found in nature. It is usually found bound in minerals with another metal, iridium.

The price for 1 gram is $41.6. There is very little of it in the earth's crust, which is why it is so expensive.

Osmium is mainly used in the chemical industry, and then in small quantities.

Physical and chemical properties

Californian is an extremely volatile metal. It exists in two polymorphic modifications. Below 600 °C the a-modification with a hexagonal lattice is stable (parameters a = 0.339 nm, c = 1.101 nm), above 600 °C the b-modification with a cubic face-centered lattice is stable. The melting point of the metal is 900 °C, the boiling point is 1227 °C.

The chemical properties of californium are similar to lanthanides. Californium halides - CfHal3, oxyhalides - CfOHal were synthesized. To obtain californium dioxide CfO2, Cf2O3 oxide is oxidized by heating with oxygen under a pressure of 10 MPa. In solutions, Cf4+ is obtained by acting on Cf3+ compounds with strong oxidizing agents. Solid californium diiodide CfI2 has been synthesized. From aqueous solutions, Cf3+ is reduced to Cf2+ electrochemically.

Gold $56.9 per 1 gram - 5th place.

Gold bars

Gold has been known since ancient times. It remains the most popular metal in the world. Gold is found only in its pure form. It is ideal for making jewelry. And the average cost of gold per 1 gram is $56.9.

Platinum $69.1 per 1 gram - 4th place.

This noble metal is also called white gold. It is also known as gold since time immemorial. Platinum is not found in its pure form - most often in alloys with other substances. The metal is used in jewelry, coin making, medicine and technology.

Natural substances:

Rhodium

$225 per gram

One of the rarest on Earth. Silver-colored metal with strong reflective properties. There is an external resemblance to aluminum, but rhodium is much harder. It has high chemical resistance and is an excellent catalyst, which determines its main use in the chemical and automotive industries. In jewelry production, rhodium is used in the final processing of products.

Platinum

$70 per gram

Silver-white metal. Previously, due to its refractoriness, it was valued lower than silver. The metal has not been found in its pure form on Earth. Most often, platinum is found in the form of alloys with other metals. Platinum is isolated through a complex chemical process. Along with jewelry production, platinum is used in the electronics and medical industries. Also used for making coins.

Gold

$30-40 per gram

Main precious metal. It is found in the depths only in a pure state. The malleability, strength and anti-corrosion properties of gold make it an indispensable chemical element for the production of jewelry and bank coins, and determine its use in the electronics industry and dentistry.

Osmium

$19 per gram

Silvery-white shiny metal, not found in the depths in its pure form. It has a specific odor and very high density. Very fragile. Used in the chemical industry (catalyst) and pharmacology.

Ruthenium

$15 per gram

Named after Russia (lat. Ruthenia - Russia), the silver-gray metal is very rarely found in the depths. Its properties include simultaneous hardness and brittleness, as well as refractoriness. High purity ruthenium has not yet been obtained. The characteristics of ruthenium make it in demand in jewelry production, the chemical and electronics industries.

Isotope "Osmium - 187" $10,000 per 1 gram - 2nd place.

Exists in isotope form. The price for 1 gram is $10,000, so it deserves 2nd place. It is almost never found in its pure form, and the extraction of Osmium-187 is a very long and complex process that lasts approximately 9-10 months.

The most expensive metal at the moment is California-252. There is no more than 5 grams of it in the world, so its value differs from all metals. It is radioactive and can be used as a substitute for a nuclear reactor and in many other areas and industries. If one wanted to obtain neutron radiation like that of California-252 in the classical way from a radium-beryllium source, then this would require 200 kg of radium.

Californium-252 was produced artificially in 1950 at the University of California at Berkeley. This metal is not mined in nature.

By weight California. Metal worth $250 million per gram is produced in the Ulyanovsk region

In 1960, Dr. Sten Forshufvud, a dentist from Sweden, launched a large-scale study that was completely unrelated to his specialty. He set out to prove to society that Napoleon Bonaparte did not die of depression and ulcers on the island of St. Helena, but was poisoned. The hypothesis caused a stir in the media and among historians, and the most expensive metal in the world, created a few years earlier, helped to develop it - californium.

250 million dollars for ONE(!) gram of metal. Neither gold nor platinum costs that much, even diamonds don’t cost that much. And California is worth it. Because it is the rarest metal on earth: its global reserve is about 10 g, which is not surprising, given the volume of resources needed for its production. Its cost is measured in hundreds of millions of dollars. In rubles, this number is more like a Wi-Fi password than a price. 1 mg of California costs the same as 7 two-room apartments in the historical center of Ulyanovsk with panoramic windows and European-quality renovation. It is produced only in two places on the planet - at the Oak Ridge National Laboratory in Tennessee, USA, and at the Research Institute of Nuclear Reactors in Dimitrovgrad.

Bombardment of plutonium and curium

It is believed that the California isotope is formed in huge quantities during supernova explosions. But on Earth this element does not occur naturally. It can be obtained artificially by irradiating curium targets (also an expensive artificial metal) in nuclear reactors. This is the fastest way to accumulate expensive Californian. It takes about a year and a half. The synthesis takes place in several stages with the formation of new isotopes and stops at californium, the nucleus of which is insensitive to radiation and does not increase its mass.

There are other ways - for example, bombarding (irradiating) plutonium with charged particles. To produce 1 g of californium, 10 kg of plutonium is required, which is also produced only in laboratories and 40 kg of which is enough to create 6 nuclear missiles. Plutonium successively metamorphoses into the metals americium, curium, berkelium and, finally, californium. But in this case, you will have to wait a long time: the process of producing californium even in the most powerful reactor will take as long as 8 years. And from 10 kilograms of plutonium you can get a maximum of one gram of californium.

But everything only begins with the operating time in the reactor. Ahead lies the complex radiochemical process of separating a valuable isotope from by-products. This happens in so-called hot cells. Which are actually not hot at all: the temperature here is room temperature. But security measures are increased.

The dexterity of the operator's mechanical hands is worthy of special attention.

With the help of these seemingly clumsy devices, they can light matches, thread needles and perform many other incredible operations. Of course, before they receive access to radioactive materials, they train on simulators, but even after that, not everyone is trusted to cut targets and weld capsules.

But if this story about the production of sources took us only a few paragraphs, then the process itself takes no less than 4 months. Radiochemistry does not tolerate fuss.

Instead of seven years - in a few months

Dimitrovgrad Californian is ordered by production all over the world: Turkey, China, Australia, Malaysia. Dimitrovgrad admits that orders for californium are constantly coming, but the production volumes of the isotope are limited. Buyers are put off not so much by the price as by the waiting time.

— The idea of ​​an express method for obtaining californium, as it turned out, lay nearby. Together with my colleagues, we tried to irradiate berkelium. They received California in a few months instead of seven years. To date, two deliveries of californium, produced using the express method, have already been made,” said Rafael Abdulov, junior researcher at the radiochemical laboratory of the Research Institute of Nuclear Reactors. “My colleagues and I have to solve issues related to the production of isotopes every day, look for optimal modes of technological processes, and conduct fundamental research. But sometimes we are faced with extremely difficult problems. For example, accelerating the production of the most expensive metal in the world - California-252.

CF at the service of people

The most obvious area of ​​use for Californian is medicine. In the 1960s, studies began on the effects of California-252 on malignant tumors. Experiments and studies were carried out, first on Chinese hamsters, then on humans. Now the 252nd isotope is successfully used in radiological therapy of tumors - it is expensive, but effective. A microparticle of the isotope, placed on the tip of a very thin needle, can have a targeted effect on the tumor without damaging other tissues. The well-known neutron knife works on a similar principle, but experts assure that Californian sources are much more effective than gamma and beta radiation.

California's potential is both a starting source for nuclear reactors and an indicator for new oil and gas fields. And in addition, this is a very promising isotope for the so-called neutron activation analysis - a method that allows you to determine the concentration of elements in a sample. For example, it was with the help of such an analysis that arsenic was discovered in Napoleon’s hair, which suggested that the emperor was poisoned. However, at the beginning of the 21st century, the hypothesis was refuted by finding out that the hair was stored in a powder containing arsenic, and Bonaparte himself suffered from a perforated ulcer and, probably, stomach cancer. It is unknown which disease killed him, but it is possible that exposure to Californian would have saved the exiled emperor.

In the United States, californium is used in sources that illuminate aircraft parts and reactor parts. This method of analysis is very expensive, but it allows you to determine all internal defects without disassembling the object. Cf can also serve for security: element-98 allows you to detect all types of drugs, even if they are sealed in a cartridge case, and explosives at the bottom of a freight car, thereby saving hundreds and thousands of lives.

However, experts admit that for now these are just experiments. Humanity will not begin to widely use the capabilities of California until the 22nd century. In the meantime, the supply of all Californian on earth does not exceed 11 grams.

Reference

The serial number of Cf in the periodic table is 98, the year of discovery is 1950, the place is the University of California at Berkeley, USA. Californium is synthesized artificially and is not found on Earth (but there is a version that it is formed during supernova explosions). There are 17 known isotopes (elements with the same atomic number, but a different atomic mass, that is, the number of neutrons in the nucleus of an atom).

Nadya AKULOVA

Where does californium come from?

Californium is not mined from ore like regular metals. It is produced atomically in powerful nuclear reactors designed specifically for the synthesis of transuraniums. Heavy isotopes of curium and plutonium are irradiated with a flux of neutrons. Without such irradiation inside the reactor boiler, the process of transformation of curium and plutonium into element 98 can last for years.

There are only 2 production centers for 252 California - the USA and Russia. Radioactive plutonium or curium is used as a raw material to produce Cf - it is irradiated with neutrons in a nuclear reactor. The protective casing protects personnel from dangerous radiation and electromagnetic waves of the reactor.

The transformation of plutonium and curium into californium is a multi-stage process. Each of the reactant participants decays and forms a new isotope. The entire chain of decays and synthesis can be put into the sequence:

1. Plutonium-Americium
2. Americium-Curium
3. Curium-Berkley
4. Berkeley-California.

Once Cf is formed, the transformation process dies out. Californian cannot be converted into an isotope of higher atomic weight - the nucleus responds poorly to neutron irradiation.

To obtain 1 gram of California-252, 10 kg of plutonium-239 is consumed:

• 99.7% of plutonium atoms decay in a nuclear reaction;
• 0.3% retain their atomic structure and become californium.

Californium leaves the reactor in the form of oxides and complex salts. To reduce it to metal, redox reactions are used.

To isolate 252 Cf from reaction products, methods are used

1. extraction
2. extraction chromatography
3. ion exchange.

That's why 1 gram of Cf-252 costs about thirty million dollars.

Isotopes of California

The radioactive metal has 17 isotopes with masses ranging from 240 to 256 atomic units. Everyone's life expectancy is different. Not all of them can be obtained in macro quantities, more than a few atoms.

Among the products of a thermonuclear reaction (1952) in Berkeley, California, 254 isotopes with completely surprising properties were discovered. During the spontaneous fission of its nucleus, a gigantic specific energy is released - 10,000,000 W/kg.

All the benefits of a dangerous metal

The fission process of the California-252 atomic nucleus results in the formation of 4 neutrons. Such neutron radiation can be accurately predicted, which became the basis for the practical use of the most expensive metal on Earth.

Neutron source

The main process of the isotope occurs according to the α-decay type. In parallel, spontaneous fission occurs with the release of nuclear fragments. Spontaneous processes of 1 μg of 252 isotopes produce the same number of fragment nuclei as 1 μg of uranium in a nuclear reactor under intense neutron bombardment. Therefore, the main purpose of the 252 isotope is a compact and powerful source of neutrons for physical research. For example, as a starting source of neutrons to start the operation of a nuclear reactor.

Scientific research of the micro- and macrocosm

The California isotope is indispensable in studying the structure of matter and the atomic nucleus. The knowledge gained is applicable not only to terrestrial conditions: in deep and near space exploration, neutron radiation from 252 isotopes is used.

applied Science

The neutron emission of California-252 is used in geological exploration and mining of silver and gold. These rays make it possible to create a map of deep aquifers and oil-bearing layers of the earth's crust through analysis of the spectrum of reflected neutron radiation, neutron logging.

The constancy of neutron emission is widely used in studying the structure of various materials. A whole branch of non-destructive flaw detection, neutron radiography, has emerged. By simple surface irradiation it is possible to monitor the safety of nuclear reactors, parts of space and aviation equipment and other structures. This technique allows you to detect the initiation of microcracks long before the onset of destruction and take timely measures.

Daily Practice

A portable version of the neutron radiograph is available in the police arsenal. The device finds cleverly hidden drugs that X-rays could not detect.

Neutron sensors based on Cf-252 effectively measure humidity in automatic mode.

California-252 radiation is used to study the structure and properties of materials for the needs of the coal industry, metallurgy and petrochemistry.

Medicine

Neutron radiosurgery is a proven, highly effective method of treating oncology. A very thin needle with microscopic grains of Cf-252 is inserted into the tissue of a cancer patient. The flow of slow neutrons destroys atypical cells without causing harm to healthy ones. The malignant tumor is treated locally with a high degree of precision.

Californian saved many lives and gave hope to thousands of patients to be cured without traumatic operations.