Birthstones are a fascinating aspect of the gem and jewelry world, and are derived from early beliefs regarding the one’s time of birth and its relationship to the planets. Wearing a certain stone as protection against illness and misfortune, or another gem for good luck, eventually developed into the birthstone systems of today.

Modern Birthstones
From these early systems, comes the modern birthstone system.

The Western birthstone system originates from the writings of Jesephus (1st century AD) and St. Jerome (5th century AD). Both trace the custom to the gems of the Hebrew High Priest’s Breastplate. Over time, the birthstone custom died, only to be revived again in 18th-century Poland.

Zodiac Gems
Long before the modern 12-month calendar was invented, astrologers assigned certain gemstones to the 12 signs of the zodiac based on the symbolism and metaphysical powers each stone was believed to possess.

Sign	Sign	Zodiac Stone		Sign	Sign	Zodiac Stone
	Capricorn Dec. 22–Jan. 20	Ruby			Cancer June 22–July 22	Emerald
	Aquarius Jan. 21–Feb. 21	Garnet			Leo July 23–August 22	Onyx
	Pisces Feb. 22–March 21	Amethyst			Virgo August 23–Sept. 22	Carnelian
	Aries March 22–April 20	Bloodstone			Libra Sept. 23–Oct. 23	Peridot
	Taurus April 21–May 21	Sapphire			Scorpio Oct. 24–Nov. 21	Beryl
	Gemini May 22–June 21	Agate			Sagittarius Nov. 22–Dec. 21	Topaz

Indian Planetary Gemology
In ancient India, beliefs regarding the planets and their relationships with stones also is found. This has developed into what some today refer to as “planetary gemology”. In such systems, there are nine planets and nine gems, as shown below. Sometimes jewelry is made using one each of these gems and are termed navaratna jewels (nava = nine; ratna = jewel).

Sign	Planet	Hindu Planetary Stone		Sign	Planet	Hindu Planetary Stone
	Sun	Ruby			Venus	Diamond
	Moon	Pearl			Saturn	Blue Sapphire
	Mars	Coral			Rahu (moon’s north node)	Hessonite Garnet
	Mercury	Emerald			Ketu (moon’s south node)	Cat’s Eye
	Jupiter	Yellow Sapphire

Birthstones for days of the week
Most Latin-based languages connect each day of the week with one of the seven “planets”: Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn. The French, for example, uses the following:

Gems for all seasons

Choosing a birthstone
If nothing else, the above should make clear that there are a bewildering variety of birthstone choices, depending on nationality, culture, religion, etc. Which one is right for you? We suggest that, if none of the above birthstones strikes your fancy, you simply choose a personal gemstone that symbolizes a special time for you. Choose a personal gemstone based on your zodiac sign, the day of the week on which you were born or the color designated for your birth month.

Size to Weight conversions   Gemstone Enhancements   Gemstone Care  Special order stones available upon request. Cabochones in various sizes available. All above weights are based on average depth and girdle thickness. Larger stones are subject to a wider weight range.