Editorial Feature
Properties This article has property data, click to view

An Overview of Mercury

Alexey V Smirnov / Shutterstock

Ancient Chinese and Hindus were familiar with mercury (Hg). The metal was also found in Egyptian tombs of 1500 BC. Mercury rarely occurs as such in nature. The primary ore of mercury is cinnabar (HgS), where the metal is extracted by heating the ore in an air current, and then condensing the vapor.


Mercury is heavy and has a silvery-white appearance. It is the only metal to exist in a liquid state at room temperature. Although it does not react with oxygen at normal temperatures, it absorbs oxygen close to the boiling point. Upon oxidizing, it transforms into a red crystalline powder called mercuric oxide (HgO).

When compared to other metals, mercury is a bad conductor of heat; however, it is a fair conductor of electricity.

Numerous compounds are formed by mercury, some of which are explosives, while all are poisonous. Mercury 203 is radioactive.


Mercury is used for the following:

  • Mercury-vapor lamps
  • Separating silver and gold from their ores
  • Tanning
  • As an expansive metal in thermometers
  • Circulating medium in atomic reactors
  • Batteries
  • Coating mirrors
  • Diffusion pumps
  • Advertising signs
  • Mercury-vapor motors
  • Amalgams
  • Frozen-mercury molding process

Different compounds of mercury are used in:

  • Pharmaceuticals—for example, black mercurous oxide (Hg2O) is used in skin ointments, and Mercurochrome (C20H8O6Na2Br2Hg)—a green crystalline powder that becomes splendid red upon being dissolved in water—is used as an antiseptic
  • Paint pigments—for example, mercury sulfide (HgS), is a bright red pigment
  • Fungicides
  • Explosives
  • Mercuric chloride (HgCl2)—a highly poisonous white crystalline powder that dissolves in water and alcohol can be used as an insecticide and rat poison, as a mordant, as a wood preservative, as a caustic antiseptic in medicine, and in tanning

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Your comment type

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.