What is special about rare earth magnets?
What's the difference between a rare-earth magnet and a regular magnet? 

The main difference between rare-earth magnets and regular magnets lies in their composition and magnetic properties:

  1. Neodymium magnets are made from alloys of rare-earth elements, such as neodymium, praseodymium, and dysprosium, along with other metals like iron and boron. In comparison, conventional magnets are usually made from materials such as iron, steel, nickel, or cobalt. However, these materials are not as strong as rare-earth elements when it comes to magnetic properties.
  2. Rare-earth magnets are particularly strong, with higher magnetic flux density and stronger magnetic fields compared to regular magnets.
  3. These magnets are much stronger than regular magnets, even though they are smaller and lighter. This makes them a great choice when size and weight are important factors. Regular magnets, on the other hand, are typically bigger and heavier than rare-earth magnets, which means they need more material to create a similar magnetic field.
  4. Rare earth magnets are used in high-tech industries and products, such as electric motors, generators, headphones, speakers, magnetic resonance imaging (MRI) machines, and magnetic levitation (maglev) trains, where strong magnetic fields are required. On the other hand, regular magnets are used in everyday applications, such as refrigerator magnets, magnetic toys, compass needles, and magnetic closures in consumer products. They are also used in industries such as manufacturing, construction, and automotive, but usually in less demanding applications than rare earth magnets.
How long do magnets last?
Rare earth magnets, such as neodymium magnets, are very strong and long-lasting. If handled and maintained properly, they can last for many years, even decades, without losing their magnetism. However, several factors can affect their lifespan. The quality of the magnets is important. High-quality magnets that are made using advanced processes and quality control measures generally last longer than lower-quality magnets. Environmental factors can also affect the lifespan of rare earth magnets.
They are sensitive to extreme temperatures, moisture, and corrosive substances. Exposure to high temperatures can weaken their magnetic strength over time, while moisture and corrosive substances can cause them to degrade. It's important to protect them from these harsh conditions to extend their lifespan. They are also brittle and can be easily damaged if subjected to mechanical stress, such as impacts or bending. Proper handling and installation techniques can help prevent physical damage and extend the lifespan of the magnets.
Lastly, the intensity and frequency of use can affect their lifespan. Magnets used in high-stress applications, such as motors or generators, may wear out faster than magnets used in less demanding applications, like refrigerator magnets. Lastly, rare earth magnets can lose their magnetism if exposed to strong magnetic fields or improper magnetization techniques. Proper magnetization and minimizing exposure to demagnetizing factors can help maintain their magnetic properties over time.
What is a neodymium magnet used for? 
Electric Motors and Generators,  Speakers and Audio Equipment,  MRI Machines,  Hard Disk Drives, Magnetic Separators,  Wind Turbine,  Automotive Sensor, DIY projects (knife or tool hanger, key hanger, numerous scientific experiments) 
What is the advantage and disadvantage of neodymium magnets? 
Advantages - Strong Magnetic Strength,  Compact SizeVersatility,  High Resistance to Demagnetization,  Wide Range of Applications.
Disadvantages - Susceptibility to Corrosion,  Brittleness, High Cost,  Temperature Sensitivity,  Magnetic  interference with other devices.
Are neodymium magnets illegal in the USA?
Neodymium magnets are not illegal in the United States. However, there are regulations governing their sale, use, and importation due to safety concerns, particularly regarding ingestion by children and potential hazards when used improperly.  While neodymium magnets are widely available for various applications, including industrial, commercial, and consumer electronics, sellers and manufacturers must comply with safety regulations and labeling requirements to ensure their safe use. It's essential for consumers to follow safety guidelines and use caution when handling neodymium magnets, particularly around children, to prevent accidents and injuries.
What kind of magnets are the strongest?
Neodymium magnets are the strongest permanent magnets available in the market. They are also called neodymium-iron-boron (NdFeB) magnets. These magnets are widely used in applications that require high magnetic performance. They are recognized for their exceptional strength, which is much higher than ceramic (ferrite) magnets and Alnico magnets. Neodymium magnets can produce magnetic fields that are several times stronger than traditional magnets. These magnets are used in various applications, including electric motors, magnetic separation, magnetic levitation, audio speakers, and magnetic resonance imaging (MRI) machines. However, they are more brittle and corrode easily, which makes it necessary to handle them carefully and coat them with protective material in certain applications.
What is the difference between a neodymium magnet and a regular magnet? 
Composition Mostly. Neodymium magnets are a type of rare-earth magnet. They are made by combining neodymium, iron, and boron. These magnets are known for their exceptional strength, producing magnetic fields that are several times stronger than other types of magnets. They are used in various demanding applications, such as electric motors, magnetic resonance imaging (MRI) machines, audio speakers, and magnetic levitation systems. On the other hand, regular magnets are made of different materials like ceramic, aluminum, nickel, cobalt, and iron. These magnets are less powerful compared to neodymium magnets but still serve different purposes. For instance, they are used in everyday applications like refrigerator magnets, magnetic closures, educational toys, compasses, and various industrial applications. To sum up, neodymium magnets are known for their extraordinary strength and are commonly used in demanding applications. Regular magnets, however, encompass a broader category of magnets with varying strengths and compositions suitable for different uses.
Is there a magnet stronger than neodymium?
Neodymium magnets are some of the strongest permanent magnets available for commercial use. However, scientists are constantly researching and developing new materials and technologies, which could lead to the discovery of even stronger magnets in the future. Some of the latest developments include rare-earth magnets made with materials like dysprosium or praseodymium. These magnets, called rare-earth permanent magnets, may offer higher coercivity and resistance to demagnetization, which are important for specific applications. Scientists are also exploring novel magnet materials, like magnetically ordered materials or composite magnets, that could exceed the capabilities of conventional neodymium magnets. However, these advancements are still in the research and development stage and are not yet widely available for commercial use. While neodymium magnets are currently the strongest commercially available permanent magnets for practical use, ongoing research and innovation may lead to even stronger materials in the future.