Holmium

Holmium is a shiny, silver metal.

It is very soft. It is hard to find in nature. It is often found in rocks.

This metal can react with things. If it touches air, it turns yellow. It can also burn when it is hot.

Holmium is very good with magnets. It helps make the strongest magnets.

It can also be used in lasers. It can even be used in glass.

Scientists found it a long time ago. It is a very special metal.

Holmium is a shiny, silver metal. It is part of a group called lanthanides. This group includes many rare metals.

Holmium is very soft and easy to shape. It is also quite rare. It makes up only 1.4 parts per million of the Earth's crust.

You can find it in minerals like monazite and gadolinite.

This metal reacts with its surroundings. If it sits in the air, it forms a yellow coating. This coating is called an oxide. It looks a bit like rust on iron. Holmium also reacts with water. It can even burn when it is heated in the air.

Holmium has special powers. It has the highest magnetic permeability of any element. This means it is very good at working with magnets. Scientists use it to make the strongest magnets. It can also be used in lasers. Some types of glass use holmium to change colors.

It is also used in nuclear reactors. It helps by absorbing neutrons. This makes it a useful tool for science.

Holmium is a very special chemical element. It has the symbol Ho and the atomic number 67. This metal belongs to a group called the lanthanides. It is the eleventh member of that series. Holmium is a rare-earth element. It is a soft and silvery metal. You can also shape it easily because it is malleable.

This metal reacts with the world around it. In the air, it forms a yellowish oxide coating. This coating looks a bit like rust on iron. When it is in dry air, it stays stable. However, it reacts quickly with water. If you heat it, the metal will actually burn in the air. It is often found mixed with other rare metals like thulium.

People discovered holmium in the year 1878. A Swedish chemist named Per Theodor Cleve found it. He was working with a material called erbia. At the same time, two others found it too. Jacques-Louis Soret and Marc Delafontaine saw it using light. They called it "Element X" at first. Cleve named it after Holmia. That is the Latin name for Stockholm.

Holmium is quite rare in nature. It makes up 1.4 parts per million of the Earth's crust. This is a similar amount to tungsten. You can find it in minerals like monazite and gadolinite. Most holmium comes from monazite sand. Scientists use a way called ion-exchange to get it out. There are about 400,000 tonnes of it in the Earth. We only produce about 10 tonnes of the metal each year.

This element has amazing magnetic powers. It has the highest magnetic permeability of any element. This means it is great for making strong magnets. It is used for the pole pieces of very powerful magnets. Holmium also absorbs neutrons very well. Because of this, it is used in nuclear reactors. It can even be used in lasers. Some special glasses use holmium to change their colors.

Holmium is a chemical element with the symbol Ho and atomic number 67. It is a rare-earth element and the eleventh member of the lanthanide series. This metal is relatively soft, silvery, and malleable, meaning it can be shaped easily. It is also fairly corrosion-resistant. However, holmium is too reactive to be found in its pure form in nature. When exposed to air, it slowly forms a yellowish oxide coating.

The chemical behavior of holmium is driven by its reactivity. In dry air at room temperature, the metal is relatively stable. If it is heated, however, it will burn in the air. It also reacts with water, corroding more quickly when the water is hot. This reaction forms holmium(III) hydroxide and releases hydrogen gas. In most laboratory settings, holmium exists in a trivalent oxidation state. This means its ions, known as Ho(III) ions, carry a +3 charge.

Holmium possesses several unique physical and magnetic properties. It is paramagnetic at standard temperature and pressure. This means it is weakly attracted to magnetic fields. However, it becomes ferromagnetic at temperatures below 20 K. Ferromagnetism is a stronger form of magnetism. Holmium has the highest magnetic moment of any naturally occurring element. It also has the highest magnetic permeability and magnetic saturation of any element. These traits make it useful for creating the strongest possible static magnets.

History shows that holmium was discovered through multiple paths in 1878. Swedish chemist Per Theodor Cleve isolated the element while studying erbia earth. He used a method to remove contaminants from the ore. This resulted in two new materials: a brown substance called holmia and a green one called thulia. Holmia was later identified as holmium oxide. At the same time, Jacques-Louis Soret and Marc Delafontaine discovered it through spectroscopy. Spectroscopy is the study of how light interacts with matter. They initially referred to the discovery as "Element X."

In nature, holmium is quite rare. It makes up approximately 1.4 parts per million of the Earth's crust. This level of abundance is similar to the element tungsten. It is found in minerals such as monazite and gadolinite.

Most commercial holmium is extracted from monazite sand. This process uses a technique called ion-exchange to separate it from other rare-earth metals. There are an estimated 400,000 tonnes of holmium in the crust. However, global production is only about 10 tonnes of metal per year.

Holmium has many specialized applications in science and industry. Because it has high magnetic permeability, it is used in the pole pieces of powerful magnets. This part is also called a magnetic flux concentrator. Because holmium absorbs neutrons very strongly, it is used as a "burnable poison" in nuclear reactors. This helps control the nuclear reaction. Its trivalent ions also have fluorescent properties. This allows holmium to be used in certain lasers and as a colorant in glass.

Specific isotopes of holmium also serve important roles. Holmium-165 is the only primordial isotope found in nature. Scientists also study synthetic isotopes like holmium-163 and holmium-166. The metastable isomer holmium-166m1 has a very long half-life of 1,133 years. It produces a rich spectrum of gamma rays. This makes it useful for calibrating gamma-ray spectrometers. Additionally, holmium oxide is used as an optical calibration standard. It is often fused into quartz cuvettes for use in spectrophotometers.