What is 24-carat gold? How will you convert it into 18-carat gold?

What is 24-carat gold? How will you convert it into 18-carat gold?
Answer:
24-carat gold is pure gold. Pure gold is very soft and not suitable for making jewellery.
Therefore, to increase its hardness, it is alloyed either with copper or silver.
18-carat gold is prepared by alloying 18 parts pure gold with 6 parts of either copper or silver.