Gold jewelry is always in the fashion. It never goes out because it is not just beautiful but friendly also. Some metals mixed with it may bring your skin some problems but gold is not often a problem. It is easy for the jewelers to work with gold as it is a kind of soft metal.
In your ring you may be able to find marks like 10k, 14k, 18k or 24k, which tells the percentage of pure gold in your ring. Higher quality of gold is marked with higher karat number. 24k gold is the purest gold. That, k stands for karat which describes the quantity of gold in you ring. In European countries the system of karat is not there. They use the numbers that point out the percentage of gold. For example, 14k is marked 585 that indicating 58.5% gold. Trademark or Hallmark on your ring indicates the purity of gold.
In gold of other qualities like 14k or 18k, some other metals like iron, copper, silver, nickel, platinum, zinc and steel are mixed to make the ring harder. Pure gold is the most expensive but the softest as no other metals are mixed with it. Platinum or copper is used to make white or yellow gold. Others metals are mixed not only to make it harder or change color, but to make the ring less costly.
For your everyday ring, solid gold is the best choice as it is durable. So, always go for 10k or 14k for your regular ring. If you have allergies against some metals like copper or nickel then look for 18k or 22k. Gold plated jewelry is also in fashion nowdays which does not cost much.