Oxygen is a gas at room temperature and does not have the following properties:

* Color: Gases are transparent, so oxygen has no color.

* Weight Density: Oxygen has a density of 1.429 grams per liter at standard temperature and pressure.

* Melting Point: Oxygen has a melting point of -218.79 °C (-361.82 °F).

* Luster: Luster refers to how light reflects off a surface, which is not applicable to gases.

* Hardness: Hardness is a measure of a solid's resistance to scratching, which is also not applicable to gases.

Let me know if you have any other questions about oxygen or other elements.