Tantalum is a chemical element with the symbol Ta and atomic number 73. It is composed of tantalum atoms with 73 protons in the nucleus. Tantalum is a rare, hard, blue-grey, lustrous transition metal that is highly resistant to corrosion. It is often alloyed with other metals to improve its mechanical properties and is used in a variety of applications, including electronics, aerospace and medical devices.

Tantalum has several notable chemical properties:

1. Corrosion resistance: Tantalum is highly corrosion-resistant, making it suitable for use in corrosive environments such as chemical processing and medical implants.

2. High melting point: Tantalum has a very high melting point, over 3000 degrees Celsius, which makes it useful for high temperature applications.

3. Inertness: Tantalum is relatively inert, which means that it does not easily react with other elements or compounds under normal conditions.

4. Oxidation resistance: Tantalum forms a protective oxide layer when exposed to air, further providing resistance to corrosion.

These properties make tantalum valuable in a wide range of industrial and technical applications.

Tantalum is formed through various geological processes. It is often found along with other minerals, such as columbite-tantalite (coltan), and is often extracted as a by-product of the mining of other metals, such as tin. Tantalum is found in pegmatites, which are coarse-grained igneous rocks that often contain high concentrations of rare elements.

The formation of tantalum deposits involves the crystallization and cooling of lava and the subsequent concentration of tantalum-containing minerals through geological processes such as hydrothermal activity and weathering. Over time, these processes form tantalum-rich ores that can be mined and processed to extract tantalum for a variety of industrial and technical applications.

Tantalum is not inherently magnetic. It is considered to be non-magnetic and has a relatively low magnetic permeability. This property makes tantalum useful in applications where non-magnetic behavior is required, such as in electronic components and medical devices.