Gold rings come in a number of different carats. A Carat is the measure of how pure a precious metal is. Thus, the higher the carat of the metal, the purer it is. Thus, 24 carat gold is the purest gold you will find. You will however find this gold available only in bullion bars. It is not present in jewelry as at 24 carat gold tends to be extremely soft and can therefore not withstand the daily wear and tear that jewelry go through over the years.
14K, or 14 carat gold, is thus made of 58.3% of pure gold. The remaining 41.7% of the ring is made of other metal. This other metal is thus what makes the ring strong and durable, as well as adds other desirable properties to the ring.
14K gold rings tend to be cheaper than 18K gold rings due to the fact that 18K due to the fact that the 18K gold ring has more pure gold content; 75% to be precise, than 14k gold ring. The 14K gold ring is however less vivid and more resistant to tarnish than the 18k gold ring. The 14K gold ring is used to make most common gold rings that most people can afford, while the 18K gold rings are much pricier and finer.
With this information, one can decide wisely on which carat gold to buy for their big day. 14K gold rings are widely used in the US as they withstand much wear and tear, while the 18K gold rings are used in Asia and Europe.