Question

What are the favorable qualities given to gold when it is alloyed with copper or silver for the purpose of making ornaments?

Answer 1

Pure gold:

• A $24$ Karat gold is $100\%$ pure gold and does not have any other metal mixed.
• It is ductile as well as malleable in nature.

An Alloy of Copper $\left(\mathrm{Cu}\right)$ and Gold $\left(\mathrm{Au}\right)$:

• Tumbaga is an alloy made up of gold and copper.
• The melting point of this alloy is lower than gold or copper alone and also it is more malleable thus it is used for making ornaments.
• It could range from $95\%$ copper to $95\%$ gold.

An Alloy of Silver $\left(\mathrm{Ag}\right)$ and Gold $\left(\mathrm{Au}\right)$:

• The alloy of silver and gold is known as Electrum.
• It is made up of $20\%$ silver and $80\%$ of gold.
• It is soft and malleable thus, it is used in making coins and ornaments.