OK here are five things to know when buying an August birthstone mothers ring.

August Birthstone

Those born in August have the birthstone peridot -- a green stone that results from volcanic activity -- and as a result is considered to represent vitality in nature and strength in relationships. It was considered the stone of the sun in ancient times because of its clarity when shown up to the sun, and its ability to shimmer after the sun went down.

August Birthstone Buying Advice

The good news if you are buying an August birthstone mothers ring is that peridots are not too expensive and are not considered rare. They come in various shades of green -- the more valuable ones are the colors of limes and are not cloudy when you look at them.

The "Evening Emerald"

It is thought that peridots were given the nickname "the evening emerald" because they would glow at night and be more easily seen by miners. More good news: It is thought that Napoleon gave a peridot ring to his wife Josephine as a symbol of his love. Bad news: He later left her.

August Birthstone CostBecause they are not too rare, a peridot with a good cut -- meaning that it dazzles-- and decent clarity -- it's not too hazy inside -- can run about $5,000 for 5 carat size or more. But a nice sized peridot can be had for well under $300, and you'll be sacrificing by taking a darker color with less stunning cut to it. But relax -- even a serviceable decent sized stone for a mother's ring can be had for under $100.

August Birth Month Flower

Along with your August mothers ring, you'll want to give them to mom with a bunch of gladiolas, the official flower of the month of August, when they bloom.

Alternate August Birthstone

Sardonyx is considered an alternative to peridot and typifies happiness in a relationship. The stone is in the quartz family and usually has red or brown bands. You may want to design a mothers ring by starting with the peridot in the center surrounded by a stackable band wrapped in sardonyx.

After selecting your stone, keep in mind that you still have more mothers ring designs to consider. Should you get it engraved? How about a stackable mothers ring if you have more than one child -- or expect more to come? There are also gold and silver ring bands to consider, and plenty of mothers rings designs and settings to browse online before making your choice.