*Brass* - The barrel of the pen is usually made of brass. Brass is an alloy of copper and zinc. It is strong, durable, and corrosion-resistant.

*Steel* - The ballpoint tip is made of steel. Steel is an alloy of iron and carbon. It is hard and wear-resistant.

*Plastic* - The cap and other parts of the pen are made of plastic. Plastic is a synthetic material that is lightweight, durable, and inexpensive.

*Ink - The ink is made of a mixture of dyes, pigments, solvents, and resins. The dyes and pigments give the ink its color. The solvents and resins help the ink to flow smoothly and dry quickly.

*Tungsten carbide* - The ball in a ballpoint pen is made of tungsten carbide. Tungsten carbide is an extremely hard material that is resistant to wear and corrosion. It is also very dense, which helps to keep the ball from bouncing or skipping when writing.

*Other elements* - In addition to the main elements listed above, ballpoint pens may also contain other elements such as nickel, chromium, and copper. These elements are added to improve the performance of the pen or to give it a different appearance.