Mercury is most commonly used in the manufacture of industrial chemicals and in electronic or electrical products. Mercury is also used in thermometers, especially those that measure high temperatures. More and more gaseous mercury is still used in the manufacture of fluorescent lamps, while many other applications are being phased out due to health and safety concerns and replaced by the less toxic but much more expensive Galinstan alloy. Other uses of mercury include:

Gold can be broken down from its minerals, so it is often used in gold mines.

It is used to make instruments such as barometers and diffusion pumps.

Gaseous mercury is used in mercury vapor lamps.

Used to make liquid mirror telescopes. A telescope that uses rotation to make liquid form a paraboloid and uses it as the main mirror for astronomical observation. The price is one third of that of an ordinary telescope.

Other uses: mercury switches, insecticides, processes for the production of chlorine and potassium hydroxide, preservatives, as electrodes in some electrolytic devices, batteries and catalysts.