For May the gemstone is the brilliant green Emerald. It's referred to as the nature stone or Venus' gem. It is also called the Gem of Eternal Spring because of its green color.
This mesmerizing gemstone is surrounded by rich lore. The ancients loved the emerald as the gemstone symbolizing love and rebirth. Roman lapidaries kept them on their worktables to rest their ees. In India, the gemstones were ground up and taken as a laxative, as a remedy for heartburn and to ease the pangs of childbirth, and as an elixir against old age. Like a one-a-day vitamin--it was good for what ailed you.
According to legends an emerald will strengthen memory, quicken intelligence and assist in predicting the future, as well as give the owner the gift of eloquence. Oh, I like that one.
Like almost all green stones, the emerald is also considered advantages for business/money ventures. They can be used to promote sales and cash flow by visualizing the flow of green money into the cash drawer. When doing this visualization, you are to wear an emerald around your neck.
In King Arthur's time, the Holy Grail was said to be carved from a large emerald, and became the symbol of chastity. In fact, it was believed that this pristine gem would break apart in the presence of lust, so wearers were forced to choose between the emerald and their passions. It was also used to reveal adultery, since it was said to glow dark when a lover was faithless. Or, if your lover betrays you, it will shatter.
For those of you born in the month of May, enjoy your wonderful birthstone. It's a powerful stone.