What is red and white gold?

Pure gold (24 carat) is soft and can not used to make jewels. In India, it is normally 22 carat and in Europe it is 14 carat and very rarely 18 carat.

It is always the metal in the alloy that makes the colour different.

Normally copper, silver and other base metals form the gold alloy.

• Copper is the most common metal and it forms a red alloy.
• 25% copper in the antique created a rose gold.
• Iron alloys with gold gives blue gold.
• Aluminium and gold give purple gold alloy.
• 14 carat and 18carat with silver give a greenish yellow gold.
• The white gold alloy is made with palladium or nickel.

This is the story of gold colours.

What are the applications of ozone?

Ozone is a pollutant, but it has many industrial applications. They include:.

• As a disinfectant in hospitals, food processing factories and aged care homes
• Water disinfectant in place of chlorine, also in swimming pools
• To kill bacteria in food
• Washing of fresh fruits and vegetables to kill bacteria, mould and yeast
• In chemical synthesis in the industry
• Used to remove the contaminants such as iron, arsenic, hydrogen sulphide and nitrites in water
• Clean and bleach industrial plants.
• In processing plastics
• Ozone is also used in bleaching wood pulp.
• It is also used to detoxify cyanide wastes from gold and silver mining.

There are several other applications because of the high oxidation potential of ozone.