Because gemstones have been valued throughout recorded history for their beauty and rarity, they have also become associated with objects and events. There are gemstones associated with each of the nine planets. There are gemstones associated with astrological signs, days of the week, and wedding anniversaries. However, the most well known association with gemstones is the birthstone.

The idea of a stone associated with the twelve months began to evolve long ago – with the breastplate of Aaron.

Prior to 1300 B.C., gemstone legend and lore focused on mystical properties associated with gems. Gems were worn to bestow those properties upon the wearer. Thus, a person plagued by nightmares might choose to wear peridot as protection against them and a woman hoping to have a child might wear emerald for fertility. Other legends grew to explain the origins of the gem. For example, amethyst was said to have been created by the Greek god of wine, Bacchus. This happened with a beautiful young woman cried out to the goddess Diana for protection against the murderous wrath of Bacchus. Diana changed the woman into a beautiful clear crystal. Bacchus then poured his wine onto the crystal, changing it to purple. Because of Bacchus’ hand in the creation of amethyst, it was used as a protection against drunkenness.

According to Biblical scripture, the priest Aaron was to wear a breastplate adorned with twelve gems, chosen by God to represent the twelve tribes of Israel. There has been some debate about which gems actually appeared in the breastplate. This is because people did not always classify gemstones by mineral composition. In fact, the most frequent ancient method of classifying gems was by color, leading to confusion between such gems as garnet and ruby.

The idea of having gemstones represent specific desirable traits found in the twelve tribes of Israel led to the association between gemstones and signs of the zodiac.

The gems chosen have changed many times through the centuries. For example, the Ancient Babylonians associated diamond with the astrological sign Libra. However, to the Greeks, diamond was associated with Cancer and, to the Byzantines, diamond was linked to Aries. The jump from stones associated with astrological signs to being associated to specific months came with the spread of Christianity.

Since the church desired to downplay the use of astrology, gemstone lore became associated with the twelve apostles. Then came a belief that people born in a certain month were assigned a specific guardian angel. Certain gems became associated with each angel, and thus the birthstone concept was born.

Originally, wealthy Europeans owned one of each “birthstone,” and changed which birthstone they wore each month in order to be in harmony with the celestial spirits. As the months changed, the wearer hoped the stone would bring the special properties during that month. Each stone had certain traits and protections ascribed to it by legend. Garnet would bring the wearer tranquility and protect against fevers and against harm during travel. Ruby would bring the clarity of mind and protect against harm from natural causes.

It was not until the 18th century that the idea of gemstones as birth amulets became popular. The logic behind the change is obvious; ownership of large numbers of gemstones was not a practice that could be embraced by most people, and eventually it became the fashion to wear only the stone associated with one’s birth month. One legend even suggested that it is unlucky for anyone who is not born in October to wear opal, but for those born in its month, opal would bring joy and contentment and protect against diseases of the eye.

The stones associated with each month have changed frequently. One reason is that identification of gemstones has been haphazard and often based on color, not composition of the stone. Also, birthstones have varied from country to country. And as people became more interested in wearing birthstones, less expensive stones have been substituted for some of the most rare gems. Finally in 1912, the National Association of Jewelers assigned the standard birthstones we recognize today. However, even in this list there were choices. A person born in March could choose between aquamarine and bloodstone, while someone born in June has the most choices with pearl, alexandrite and moonstone being equally acceptable.

Since the choice of “official” birthstones has been rather arbitrary, individuals could choose instead to wear “signature” stones based upon different standards. For example, a person who values courage might choose diamond as his signature stone since diamonds are said to ensure bravery for the wearer. (Diamond is also a symbol of fidelity in love, which is why they have become the special stone for engagement rings.) A different person might choose to wear the gem associated with their “guardian angel.” For example, a woman born in January is said to be looked after by the angel Gabriel, whose stone is onyx. Someone with a special affection for astrology might chose to wear the stone associate with her star sign. For example, a Libra may choose to wear peridot. There are also stones associate with seasons and days of the week.

With the huge number of “correct” choices available to each person, the wearing of a birthstone can be individual and distinctive. Whatever stone is chosen, one thing is certain, the stone has a rich mythic tradition that can add depth and interest to your choice.