Gold is a soft, dense and the most malleable and ductile metal. One gram of gold can be beaten to one square meter sheet. Pure gold has a bright and attractive yellow colour. As a precious metal, for centuries, it has been used as money, crisis-free investment and above all in jewellery. It is also used in the industry as well as in the medicine. Gold dissolves in mercury to form amalgam alloy, but does not react with it.

The uses of gold include:

• In several countries it is a monetary reserve.
• We know its value in jewellery.
• Gold leaf or flakes (E175 in EU) are used in gourmet foods or sweets or in juice or alcoholic fruit drinks.
• In the alternative medicine, it is very often used (e.g., Thanga pashpam).
• It is used in the dentistry to make the crown and bridges.
• Colloidal gold is used as medicine for arthritis.
• It is used as a thin thread in silk sarees and in embroidery works.
• Used in electrical connector and electronic cable.
• Used in computers of the spacecraft and jet aircraft
• Its resistance to corrosion makes it useful in several industries.
• Gold medal is a part of honour-Nobel Prize, Olympic medals, etc.
• It is also the protective coat in artificial satellites as a reflector of electromagnetic radiation.
• Used in high quality CDs

Gold is not toxic and its cyanide salts are poisonous. But, patients who are taking gold as a medicine develop toxic effects and this is approximately 25% of them. Gold plays a role in kidney problems, gold influenza, proteinuria and skin toxicity. In extreme cases, I have seen very strong deposits of metallic gold in the eyes.

In white gold alloy, the nickel present can cause contact allergy problems and persons who are having this problem should be careful with nickel or nickel alloys.