Which of the following is an ore of mercury?

• (A) Bauxite
• (B) Haematite
• (C) Cinnabar
• (D) Dolomite

To determine which of the options is an ore of mercury, let's look at each choice closely. The correct answer is (C) Cinnabar. Cinnabar is the primary ore from which mercury is extracted, and it has a distinctive red color due to its mercury sulfide composition (HgS).

Understanding Mercury Ores

Ores are naturally occurring solid materials from which a metal or valuable mineral can be extracted profitably. In the case of mercury, cinnabar is the most significant source. Let’s break down the options provided:

• Bauxite: This is the principal ore of aluminum, not mercury. It primarily consists of aluminum oxides and hydroxides.
• Haematite: This is an iron ore, mainly composed of iron oxide (Fe2O3). It is a major source of iron but has no relation to mercury.
• Cinnabar: As mentioned, this is the main ore of mercury, containing mercury sulfide. It is often found in volcanic regions and has been used since ancient times for extracting mercury.
• Dolomite: This is a type of limestone composed of calcium magnesium carbonate. It is used in construction and as a source of magnesium but does not contain mercury.

Why Cinnabar is Unique

Cinnabar is not only important because it is the primary source of mercury, but it also has historical significance. In ancient China, it was used to create vermilion pigment, which was highly valued in art and decoration. The extraction process involves heating cinnabar to release mercury vapor, which can then be condensed into liquid mercury.

Environmental Considerations

While mercury is valuable for various applications, including thermometers and dental amalgams, it is also highly toxic. The mining and processing of cinnabar must be managed carefully to minimize environmental impact and health risks associated with mercury exposure.

In summary, among the options provided, cinnabar is the only ore of mercury, making it a crucial mineral for both historical and industrial purposes. Understanding the properties and uses of different ores helps us appreciate the significance of minerals in our daily lives and the environment.