There is a birthstone for each month of the year. As the astrological signs overlap two months, each birthstone is associated with two signs of the zodiac (and the same is true for the birth color, which is the color of the stone or crystal of the month of the year).
Here is the list and description of the twelve zodiac birthstones, their color and the astrological signs that correspond to them.
Stone of birth: the garnet.
Garnet Garnet is a silicate of variable color: red-brown, dark green or even black. The chemical composition of garnet is also very variable; The main types of garnet are: pyrope (Mg3Al2Si3O12), almandine (Fe3Al2Si3O12), spessartine (Mn3Al2Si3O12), andradite (Ca3Fe2Si3O12), the grossular (Ca3Al2Si3O12) and uvarovite (Ca3Cr2Si3O12). With a hardness of 6 to 7.5 on the Mohs scale, the garnet crystallizes according to the cubic system. Garnet has been used in jewelery for thousands of years – its use is lost in the mists of time. Among the ancients, the garnet symbolized sincerity and loyalty, and it was believed that it could offer protection against injuries.
Being the birthstone of January, the garnet is associated with the astrological signs Capricorn and Aquarius.
AmethystThe amethyst is a purple to purple silicate. In reality the amethyst is a variety of quartz (rock crystal) whose chemical composition is SiO2. The color of the amethyst is due to the traces of iron which enter into its composition. Among the ancients, it was believed that the amethyst offered protection from drunkenness and possessed the virtues of spiritual healing.
Being the birthstone of February, amethyst is associated with astrological signs Aquarius and Pisces.
Aquamarine Aquamarine is a silicate of a generally greenish blue color. Of great hardness (7.5 to 8 on the Mohs scale), the aquamarine crystallizes in the hexagonal system and has the chemical composition Be3Al2Si6O18. The elders believed that aquamarine had soothing qualities and favored abundant catches during sea fishing.
Being the birthstone of March, aquamarine is associated with the astrological signs Pisces and Aries.
Stone of birth: the diamond.
DiamondThe diamond is composed of carbon crystallized according to the cubic system. The diamond is the hardest of natural minerals (10 on the Mohs scale), and its legendary adamantine luster is due to a very high refractive index (3,517). The diamond symbolizes unity and reconciliation.
Being the birthstone of April, the diamond is associated with the astrological signs Aries and Taurus.
Stone of birth: the emerald.
EmeraudeThe emerald, a green mineral, is a variety of beryl. The emerald is of high hardness (7.5 to 8 on the Mohs scale) and is a silicate of aluminum and beryllium with chromium of the chemical formula Be3Al2 (SiO3) 6 :: Cr. Emerald is used in jewelery from ancient Egypt, and it was attributed the power to cure certain diseases, such as epilepsy.
Being the birthstone of May, the emerald is associated with the astrological signs Taurus and Gemini.
Stone of birth: the pearl.
PearlThe pearl is not a stone properly speaking, but rather a concretion of calcium carbonate (CaCO3) produced by certain molluscs, such as oysters, during the intrusion of a foreign body. The mixture of minerals aragonite and calcite, which make up the pearl, is called mother-of-pearl. In many cultures, the pearl symbolizes femininity and fertility.
Being the birthstone of June, the pearl is associated with the astrological signs Gemini and Cancer.
RubyA red color, ruby is a variety of corundum. Ruby – an aluminum oxide with chromium (Al2O3 :: Cr) – is very hard (9 on the Mohs scale). When it is pure, the ruby has a great value for the jewelery. A symbol of happiness among the ancients, ruby could, it was said, heal the wounds and had a beneficial effect on cardiac function.
Being the birthstone of July, ruby is associated with the astrological signs Cancer and Lion.
Stone of birth: the peridot
PeridotThe peridot, whose color can range from yellowish green to olive green, is the name given to olivine when used in jewelery as a semi-precise stone. Of the chemical formula (Mg, Fe) 2SiO4, the peridot is fairly hard (6.5 to 7 on the Mohs scale). In ancient Egypt, peridot was thought to cure certain physical handicaps.
Being the birthstone of August, the peridot is associated with the astrological signs Lion and Virgo.
Sapphire Sapphire is the blue variety of corundum (the red variant being ruby), so it has the same hardness of 9 on the Mohs scale and the same chemical formula (Al2O3). The blue color of the sapphire comes from traces of iron and titanium. The presence of other elements can give it different colors (yellow, pink, green, white or multicolored), but the sapphire is by definition blue if no other color (eg white sapphire) is mentioned. The ancients attributed different powers to the sapphire: gift of prophecy, ability to hunt plague, etc.
Being the birthstone of September, sapphire is associated with the astrological signs Virgo and Libra.
Stone of birth: the opal
OpalThe opal is composed of hydrated silica (SiO2 * nH2O). Its water content can vary between 3% and 20%. There are many varieties of opals, color and shine very different (white, black, iridescent, orange, etc.). For the elders, the opal symbolized hope. The Egyptians of antiquity accorded it a very great value.
Being the birthstone of October, the opal is associated with the astrological signs Libra and Scorpion.
Topaz, a silicate of the chemical formula Al2SiO4 (F, OH) 2, is a fine stone found in a wide range of colors due to traces of iron, titanium, magnesium and chromium. Although its characteristic color is golden yellow, topaz can also be colorless, white, blue, greenish, brown, yellow, orange, pink, reddish or even violet. In ancient Egypt, topaz was associated, on account of its color, with the solar god Ra. In ancient India, topaz was attributed the power of balancing or controlling emotions.
Being the birthstone of November, topaz is associated with the astrological signs Scorpio and Sagittarius.
Stone of birth: turquoise
TurquoiseThe turquoise is a hydrated basic phosphate of aluminum and copper (CuAl6 (PO4) 4 (OH) 8 • 4H2O). Its characteristic greenish-blue color is given to it by copper. Turquoise has been exploited and used in jewelery for more than 2000 years. The turquoise was particularly appreciated by the Aztecs, in whom this fine stone symbolized success and wealth.
Being the birthstone of December, turquoise is associated with the astrological signs Sagittarius and Capricorn.