Birthstones are a vibrant and storied tradition, offering a unique gemstone for each month of the year. These stones serve as personal talismans, cherished gifts, and beautiful expressions of individual identity. The concept of associating a specific gem with each month has evolved over centuries, resulting in two primary lists: the traditional and the modern. While the traditional list has roots in ancient texts and historical practices, the modern list, standardized in 1912 by the American National Association of Jewelers, reflects contemporary tastes and market availability. This guide delves into the gemological properties, rich histories, and cultural lore of each month's birthstone, providing a detailed exploration for enthusiasts, buyers, and students of gemology.
January: Garnet
Garnet, the birthstone for January, is a group of silicate minerals that share a similar crystal structure but vary in chemical composition, resulting in a surprisingly diverse range of colors. While most commonly associated with a deep, fiery red, garnets can be found in nearly every hue, with the exception of blue. The name "garnet" is derived from the Latin word granatum, meaning seed, due to its resemblance to the dark red seeds of a pomegranate.
From a gemological perspective, garnet possesses a reasonably tough hardness, rating around 7 on the Mohs scale, making it a durable choice for jewelry. Its lustrous quality can range from transparent to opaque. The most common and historically significant color, red, has made garnet a symbol of passion and energy for centuries. In ancient times, it was worn as a protective talisman by travelers, as it was believed to ward off injury and ensure a safe journey. Historically, garnet was not a rare gemstone, making it accessible to a wide range of people. A particularly rare variety, the blue garnet, was a more recent discovery, first found in the 1990s, showcasing the stone's capacity for surprising variation.
February: Amethyst
The February birthstone, amethyst, is a stunning purple variety of quartz. Its color, which ranges from delicate lilac to deep, royal violet, has long captivated humanity. The name amethyst is derived from the Greek word amethystos, which translates to "not intoxicated." This etymology points to a powerful and ancient belief: that the stone could prevent drunkenness and promote clarity of mind and sober living.
Amethyst is a relatively durable gem, with a hardness of 7 on the Mohs scale, similar to garnet, and is suitable for all types of jewelry. Historically, amethyst was considered a gem of royalty, as valuable as ruby and emerald. It was favored by figures like Catherine the Great and was often used in the adornment of the British Crown Jewels. However, the discovery of large deposits in Brazil in the 19th century made the stone more abundant and affordable, allowing a broader audience to appreciate its beauty. Beyond its association with sobriety, amethyst is also linked to peace, clarity, and spiritual balance, its calming purple tones making it a timeless favorite.
March: Aquamarine and Bloodstone
March is unique in having two distinct birthstones: the serene aquamarine and the earthy bloodstone. Aquamarine, the primary modern birthstone, is a variety of the mineral beryl, making it a cousin to emeralds and morganites. Its name is a direct reflection of its appearance, derived from the Latin words for "water" and "sea" (aqua marina). The gem is celebrated for its soothing blue-to-blue-green hues, which evoke the tranquil waters of the ocean.
Aquamarine is a hard and durable gem, rating 7.5 to 8 on the Mohs scale, making it an excellent choice for jewelry that will be worn daily. Its clarity is often exceptional, with large, clean crystals being relatively common. Historically, sailors wore aquamarine as a talisman for protection against the perils of the sea, believing it would ensure a safe passage and calm storms.
The traditional birthstone for March is bloodstone, also known as heliotrope. This opaque variety of chalcedony (a microcrystalline quartz) is typically dark green with distinctive red spots of iron oxide, which were thought to resemble the blood of Christ, giving rise to its name. Bloodstone has a hardness of 6.5 to 7 on the Mohs scale. It has a long history of use in ancient civilizations, particularly in Mesopotamia and Egypt, for making seals and amulets. It was associated with courage, strength, and healing, and was believed to staunch wounds and purify the blood.
April: Diamond
The diamond, birthstone for April, is arguably the most famous and coveted gemstone in the world. Composed of pure carbon, the diamond is the hardest known natural material, ranking a perfect 10 on the Mohs scale. This exceptional hardness, a result of its tightly bonded atomic structure, gives the diamond its legendary durability and its ability to scratch any other substance.
The word "diamond" comes from the Greek word adamas, meaning "unconquerable," a fitting name for a stone that symbolizes eternal love, strength, and invincibility. While diamonds are most prized for their colorless, transparent form, they also occur in a variety of fancy colors, including yellow, pink, blue, and green. The gem's brilliance and fire, its ability to disperse light into a rainbow of colors, have made it the premier choice for engagement rings and other significant jewelry. The diamond's symbolism of enduring commitment has solidified its place as a timeless classic.
May: Emerald
The lush green birthstone for May is the emerald, a variety of the mineral beryl. Its captivating color, ranging from light to deep, vivid green, is caused by trace amounts of chromium and vanadium. Emerald is one of the most valuable and historically significant gemstones, cherished for millennia.
The emerald has a hardness of 7.5 to 8 on the Mohs scale, similar to aquamarine. However, it is known for its "jardin," a French term for garden, which describes the natural inclusions and fractures often found within the stone. These internal features are considered a fingerprint of nature, distinguishing each emerald and contributing to its unique character. Historically, emeralds were mined in Egypt as early as 330 BC and were a favorite of Cleopatra. The stone is a powerful symbol of rebirth, fertility, and love, and is associated with patience, wisdom, and growth.
June: Pearl, Alexandrite, and Moonstone
June is another month with multiple birthstones, offering a diverse selection: the organic pearl, the color-changing alexandrite, and the ethereal moonstone. The traditional birthstone, pearl, is unique among gems as it is created by living organisms. Pearls are formed within mollusks, such as oysters and mussels, as a defense against an irritant. They are composed of calcium carbonate in microscopic crystalline form.
Natural pearls are exceptionally rare, and most pearls on the market today are cultured, where a bead is intentionally introduced to stimulate pearl formation. Pearls are relatively soft, rating 2.5 to 4.5 on the Mohs scale, and require delicate care. They have long symbolized purity, innocence, and wisdom.
The modern birthstone for June is alexandrite, a rare variety of chrysoberyl famous for its dramatic color change. In daylight or fluorescent light, it appears as a bluish-green or teal, while in incandescent light, it transforms to a shade of red or purple. This remarkable phenomenon led to the saying, "emerald by day, ruby by night." Discovered in Russia's Ural Mountains in the 1830s and named after the future Tsar Alexander II, alexandrite has a hardness of 8.5, making it a very durable gem.
Also listed as a birthstone for June is moonstone, a member of the feldspar group. It is prized for its unique visual effect known as adularescence, a milky, bluish sheen that moves across the stone's surface as it is rotated. This phenomenon is caused by the intergrowth of two different feldspar minerals. Moonstone has a hardness of 6 to 6.5 and is associated with intuition, balance, and new beginnings.
July: Ruby
The fiery red birthstone for July is the ruby, a variety of the mineral corundum (aluminum oxide). Its color is derived from traces of the element chromium. The ruby is one of the most valuable and desirable colored gemstones, renowned for its vibrant, passionate red hue.
The name "ruby" comes from the Latin word rubeus, meaning red. With a hardness of 9 on the Mohs scale, second only to the diamond, the ruby is an exceptionally durable gem, perfect for rings and daily-wear jewelry. Its value is determined by the intensity and saturation of its color; the most prized rubies, often from Myanmar (formerly Burma), exhibit a rich, pure red with a subtle blue undertone, a color known as "pigeon's blood." The ruby has long been a symbol of love, passion, and power. In ancient Sanskrit, it was called ratnaraj, or "king of gems."
August: Peridot, Spinel, and Sardonyx
August is represented by three birthstones: the vibrant peridot, the diverse spinel, and the banded sardonyx. Peridot, the primary modern birthstone, is the gem-quality variety of the mineral olivine. It is one of the few gems that occurs in only one color: a distinctive lime or olive green, caused by its iron content. Peridot has a hardness of 6.5 to 7 on the Mohs scale. Ancient Egyptians called it the "gem of the sun," believing it protected its wearer from the terrors of the night and warding off evil spirits.
Spinel, the second modern birthstone for August, is a beautiful and often-overlooked gem that comes in a wide array of colors, including vibrant reds, pinks, blues, and purples. For centuries, many famous "rubies," including the Black Prince's Ruby in the British Imperial State Crown, were actually red spinels. With a hardness of 8 on the Mohs scale, spinel is both beautiful and durable.
The traditional birthstone for August is sardonyx, a variety of chalcedony (a microcrystalline quartz) characterized by its bands of reddish-brown sard and white onyx. It has a hardness of 6.5 to 7. In ancient Rome, sardonyx was a popular stone for signet rings, used to press a seal into hot wax, as its banded pattern created a striking impression.
September: Sapphire
The birthstone for September is the sapphire, a classic and regal gem that is a variety of the mineral corundum. While sapphire is most famous for its brilliant blue color, which is caused by traces of titanium and iron, the name "sapphire" in the gem trade can refer to any corundum that is not red (rubies are red corundum). This means sapphires can be found in a rainbow of colors, including pink, yellow, and green, though the deep blue remains the most iconic.
Sapphire has a hardness of 9 on the Mohs scale, making it exceptionally durable and resistant to scratching. It is second only to the diamond in hardness among naturally occurring gems. Historically, sapphire has been a symbol of wisdom, truth, and royalty. It was believed to protect its wearer from harm and envy and to attract divine favor. Its enduring beauty and strength have made it a favorite for engagement rings and crown jewels for centuries.
October: Tourmaline and Opal
October boasts two of the most colorful and dynamic birthstones: tourmaline and opal. Tourmaline is often called the "rainbow gemstone" because of its unparalleled range of colors. It can be found in every shade imaginable, and some crystals even display multiple colors in a single stone, a phenomenon known as "watermelon" tourmaline with its pink center and green rind.
Tourmaline is a complex borosilicate mineral with a hardness ranging from 7 to 7.5 on the Mohs scale, making it a good choice for jewelry. Its name is derived from the Sinhalese word turmali, meaning "mixed stones." Each color of tourmaline is believed to hold unique metaphysical properties, but the stone in general is associated with creativity and inspiration.
The traditional birthstone for October is opal, a unique and mesmerizing gem known for its "play-of-color." This optical phenomenon is the result of the diffraction of light by the silica spheres that make up the opal, creating a dazzling display of iridescent flashes. Opal is composed of hydrated silica and is relatively soft, rating 5.5 to 6.5 on the Mohs scale, requiring careful handling. The Romans considered opal to be the "Queen of Gems," as it contained the colors of all other gems. It is a symbol of hope, innocence, and purity.
November: Topaz and Citrine
November's birthstones are the golden topaz and the radiant citrine. Topaz, the traditional birthstone, is a silicate mineral that occurs in a variety of colors, but it is most prized for its rich, warm golden-orange hue. With a hardness of 8 on the Mohs scale, topaz is a durable and lustrous gem. The name may be derived from the Sanskrit word tapas, meaning fire. Topaz has been associated with strength, intelligence, and good fortune.
Citrine, the modern birthstone for November, is a variety of quartz that ranges from pale yellow to a deep, reddish-orange. Its warm, sun-kissed color has earned it the nickname "the merchant's stone," as it is believed to bring prosperity and success. With a hardness of 7 on the Mohs scale, citrine is an affordable and durable gem. Its cheerful color makes it a popular choice for jewelry, evoking feelings of warmth and energy.
December: Tanzanite, Blue Zircon, and Turquoise
The final month of the year offers a cool and captivating trio of birthstones: tanzanite, blue zircon, and turquoise. The most modern of these, tanzanite, is a relative newcomer to the gem world. It is the blue-to-violet variety of the mineral zoisite, first discovered in Tanzania in the 1960s. Its alluring color is the result of heat treatment applied to brownish zoisite crystals. With a hardness of 6.5 to 7 on the Mohs scale, it is a beautiful but slightly softer gem that requires care.
Blue zircon, another December birthstone, is the traditional alternative. It is the brownish-red gem zircon that has been heat-treated to produce a brilliant blue color. Zircon is one of the oldest minerals on Earth, and its high refractive index gives it exceptional brilliance and fire, often rivaling that of a diamond. It has a hardness of 7.5 on the Mohs scale.
The traditional December birthstone is turquoise, an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminum. Its distinctive color, which can range from sky blue to apple green, is caused by the presence of copper. Turquoise is relatively soft, with a hardness of 5 to 6 on the Mohs scale. It has been mined and cherished for thousands of years by cultures across the globe, from ancient Egypt to the American Southwest. Turquoise is widely regarded as a symbol of protection, wisdom, and good fortune.
Conclusion
The twelve birthstones, from the deep red of garnet to the vibrant blue of tanzanite, represent a rich tapestry of geological wonder, human history, and cultural symbolism. Each gem possesses a unique combination of physical properties and aesthetic qualities that have captivated humanity for centuries. Whether chosen for personal significance, symbolic meaning, or simply their intrinsic beauty, these stones connect us to the natural world and to the long-standing traditions of our ancestors. Understanding their properties, origins, and lore deepens our appreciation for these remarkable treasures of the earth.