Sometimes, it can be harder than expected to find that perfect present for her - whether the 'her' in question is a close female relative, your wife or a girlfriend that you've been with for several years. Maybe you got her a necklace for her Valentine's Day and a pair of earrings for Christmas - but don't feel that you've exhausted the gift possibilities of jewellery. Birthstones, for instance, can make a fantastic - and unique - birthday present that will lend a wonderful personal touch to her birthday.

Each month of the year is represented by a separate birthstone, each of which has its own distinct meaning. And the use of the birthstone as a symbol of good luck on one's birthday has a history which is said to stretch back as far as the first century. In 1912, the American national association of Jewellers - the Jewellers of America - created a standardised which is now widely used across the world.

People born in January have the garnet as their birthstone, a deep red stone that was originally used in thirteenth century as an insect repellent and a guard against evil spirits! Essentially, the garnet birthstone is said to represent constancy, a symbol of faith and devotion. The February birthstone - the delicate purple amethyst - on the other hand, was once considered by the Greeks as an effective antidote against drunkenness! Despite this association, the amethyst birthstone is now seen to infer sincerity.

Those born in March will have the benefit of the clear blue aquamarine as their , a precious jewel that symbolises courage - a feature that perhaps dates back to the stone's use as a "magical" antidote to poison in the Middle Ages. But April birthdays will enjoy the luxury of having the world's most stunning jewel, the diamond, as their birthstone. Diamonds have been a symbol of purity and innocence since their first discovery, with attachments to divine beings across the world. If your loved one is born in April, a diamond is sure to show them how special they are.

People with a birthday in May will take pleasure in the rich green emerald, a symbol of love and success, as their birthstone, while June birthdays will be able to enjoy the soft hues of the pearl as their unique birthday stone. The pearl symbolises health and longevity, and has traditionally been an emblem of feminine regenerative power - an aspect of this particular birthstone that's sure to have its female recipients beaming with glee.

The strong red of the ruby, July's designated birthstone, has long been associated with the passion of love. But the birthstone ruby is more than this - it also stands for contentment, freedom and charity. If your special someone has a birthday in August, you'll be able to offer them the light green peridot, a birthstone that is said to traditionally bring its wearer peace and good luck. What's more, the peridot is a symbol of marital happiness - so if your wedding anniversary is in August as well, the peridot will have a rich double meaning for your wife.

While for many, September may signal the beginning of the year's short days and long nights, people with birthdays in September will love the feeling of having the sapphire as their birthstone. One of the most beautiful blue jewels, the sapphire is conventionally believed to attract the favour of the Gods, while it represents clear thinking in the birthstone context. Opals will adorn the skin of people with birthdays in October; opals are unique in that they're available in a variety of colours and hues, and symbolise hope.

November birthdays take the topaz as their birthstone. This orangey-brown jewel has long been seen as the gemstone of spiritual rejuvenation and fidelity. Ultimately, people born in December will be able to take pleasure in the prophylactic qualities of the turquoise stone, a blue gem that is said to bring prosperity to its owner - something that's sure to come in handy at Christmas.

Birthstones can be set in a variety of jewellery type and in a range of different types of metals. So whether you're seeking sapphires set in white gold earrings for your girlfriend's birthday in September, or you're keen to find a diamond-set gold necklace for your mother's 50th birthday next April, you'll definitely be able to find birthstone jewellery to fit your budget and your special someone's personal tastes.