钋 (Polonium) is a rare and highly radioactive element with the chemical symbol Po and atomic number 84. Discovered by Marie Curie in 1898, it is found in trace amounts in uranium ores. Polonium emits alpha particles, making it hazardous to human health if ingested or inhaled. Due to its radioactivity, polonium has limited applications. It is primarily used in specialized devices, such as static eliminators and nuclear batteries. Its intense radioactivity also makes it a subject of interest in scientific research, particularly in the fields of nuclear physics and radiochemistry.