Birthstones represent a fascinating intersection of geology, history, and personal identity. These carefully selected gemstones, assigned to each month of the year, offer a colorful and meaningful way to connect with the natural world. While the modern list of birthstones is a relatively recent development, the tradition of wearing gems for their perceived protective and beneficial powers is ancient. Today, birthstones serve as popular choices for jewelry, carrying both aesthetic appeal and personal significance. This guide explores the gemstones associated with each month, detailing their unique properties, historical lore, and the traditional alternatives that have been cherished throughout history.
Modern and Traditional Birthstones by Month
The concept of a birthstone for each month has evolved over centuries, culminating in the modern lists used by jewelers today. These lists often include both a contemporary choice and a traditional alternative, providing a rich variety for those seeking a personal gem.
January: Garnet The primary birthstone for January is garnet, a silicate mineral group known for its lustrous quality. While most commonly associated with a deep red hue, garnets are remarkably diverse and can be found in a wide spectrum of colors. The gemstone has a Mohs hardness rating of approximately 7, making it a reasonably tough and durable choice for jewelry. Historically, garnet has symbolized strength and protection. The traditional birthstone for January is also garnet.
February: Amethyst Amethyst, a purple variety of quartz, is the designated birthstone for February. This gem is historically linked to concepts of clarity, peace, and spiritual balance. Ancient lore suggested it could ward off intoxication and enhance business acumen. Once a stone reserved for royalty due to its rarity, new discoveries have made amethyst more accessible while retaining its beauty. Both modern and traditional lists for February feature amethyst.
March: Aquamarine and Bloodstone March is unique in having two distinct birthstones. The modern choice is aquamarine, a gem prized for its soothing blue tones that evoke the sea. The traditional birthstone is bloodstone, a dark green jasper characterized by distinctive red specks, historically associated with health and vitality.
April: Diamond The diamond, renowned for its exceptional scintillation and hardness, is the birthstone for April. As one of the most celebrated gems in history, it symbolizes enduring love and clarity. Its unparalleled brilliance has made it a cornerstone of fine jewelry. The diamond holds its place as both the modern and traditional birthstone for this month.
May: Emerald Emerald, with its captivating and vibrant green, is the birthstone for May. This gem is part of the beryl family and is one of the most coveted and valuable colored stones. Its color is often described as mirroring the splendor of spring. Emerald is the designated birthstone for May in both modern and traditional contexts.
June: Pearl, Alexandrite, and Moonstone June is one of the few months with three official birthstones. The traditional gem is the pearl, an organic gem created by living mollusks. The modern additions are alexandrite, a rare and remarkable chrysoberyl that appears green in daylight and red under incandescent light, and moonstone, a member of the feldspar group known for its unique adularescence, or moon-like sheen.
July: Ruby The ruby, a fiery red variety of the mineral corundum, is the birthstone for July. Its name is derived from the Latin word ruber, meaning red. As one of the most valuable gemstones, the ruby has long been associated with passion, power, and protection. It is the sole birthstone for July in both modern and traditional lists.
August: Peridot, Spinel, and Sardonyx Those born in August can choose from three gems. The modern birthstone is peridot, a vibrant olive-green gem formed deep within the earth. Spinel is a modern alternative, available in a brilliant array of colors, and sardonyx, an ancient gemstone featuring bands of reddish-brown and white, serves as the traditional choice.
September: Sapphire Sapphire, the birthstone for September, is a variety of corundum celebrated for its deep blue hue. However, sapphires can occur in every color of the rainbow except red (which is classified as ruby). This gem is a symbol of wisdom, loyalty, and nobility. It is the designated gem for September in both modern and traditional usage.
October: Opal and Tourmaline October is represented by two contrasting gemstones. The traditional birthstone is opal, an amorphous silica known for its unique "play-of-color," a dazzling display of spectral hues. The modern alternative is tourmaline, a gemstone available in more colors and color combinations than any other, often celebrated for its diversity.
November: Topaz and Citrine November's birthstones are topaz and citrine. Topaz, in its pure form, is colorless but is often found in warm shades of yellow, orange, or brown. Citrine is a variety of quartz known for its pale yellow to brownish-orange hues. Both gems are celebrated for their affordability and abundance.
December: Tanzanite, Turquoise, and Zircon The final month of the year offers a trio of blue-hued gems. The modern birthstones are tanzanite, a relatively recent discovery found only in Tanzania, and blue zircon, known for its high refractive index and brilliance. The traditional birthstone is turquoise, an opaque blue-to-green mineral that has been prized for millennia.
The Historical Evolution of Birthstone Lists
The tradition of assigning a specific gemstone to each month has a long and complex history. The practice is most commonly traced back to the Breastplate of Aaron, a ceremonial garment described in the Old Testament of the Bible. This breastplate was adorned with twelve different gemstones, each representing one of the twelve tribes of Israel. Scholars believe there is a connection between these twelve stones and the twelve signs of the zodiac, which later evolved into the association with the twelve months of the year.
An early and influential text linking gems to the months was written by Flavius Josephus, a first-century historian. He suggested a connection between the twelve stones on the breastplate and the twelve months of the year, though his specific assignments differed from modern lists. This idea was further developed in the 8th and 9th centuries, and by the 16th century, the practice of wearing a specific gemstone corresponding to one's birth month had become popular in Poland and other parts of Europe.
The modern list of birthstones, as it is largely known today, was standardized in 1912 by the American National Association of Jewelers (now Jewelers of America). This list was created to provide a consistent guide for the jewelry trade and consumers. The 1912 list included gems that were commercially available and popular at the time. However, the list has been updated several times since to reflect new discoveries and changes in the market. For example, tanzanite was added as a December birthstone in 2002, and spinel was added as an August option in 2016. This evolution demonstrates how birthstone lists are not static but adapt to new information and availability.
The Science Behind the Gems: An Overview of Properties
Understanding the gemological properties of birthstones provides insight into their durability, appearance, and value. Each gem has a unique chemical composition and crystal structure that defines its characteristics.
Silicate Minerals
Many of the most popular birthstones belong to the silicate mineral group, which is the largest and most varied class of minerals in the Earth's crust.
- Garnet: As noted, garnet is a group of silicate minerals. The general chemical formula for garnet is X3Y2(SiO4)3. Its hardness on the Mohs scale is typically between 6.5 and 7.5, making it suitable for most jewelry.
- Amethyst: A variety of quartz (silicon dioxide, SiO2), amethyst has a hardness of 7 on the Mohs scale. Its purple color is caused by trace amounts of iron and other metal elements within its crystal structure, along with natural irradiation.
- Emerald and Aquamarine: Both are varieties of the mineral beryl (beryllium aluminum silicate, Be3Al2(SiO3)6). They share a hardness of 7.5 to 8 on the Mohs scale, making them relatively durable. Their colors are due to trace impurities: chromium and vanadium for emerald's green, and iron for aquamarine's blue.
- Sapphire and Ruby: These are also varieties of corundum (aluminum oxide, Al2O3). Corundum is exceptionally hard, rating a 9 on the Mohs scale, second only to diamond. Trace amounts of chromium give ruby its red color, while iron and titanium are responsible for the blue of sapphire.
- Tourmaline: A complex silicate mineral with a wide chemical range, tourmaline's hardness is typically 7 to 7.5. Its incredible variety of colors is due to the presence of elements like iron, manganese, lithium, and chromium.
Other Mineral Groups
- Diamond: The diamond is an allotrope of carbon, making it one of the simplest gems in terms of chemical composition. Its defining characteristic is its supreme hardness of 10 on the Mohs scale, the highest possible rating. This is a result of its strong covalent bonds within a cubic crystal structure.
- Peridot: A variety of the mineral olivine ((Mg,Fe)2SiO4), peridot has a hardness of 6.5 to 7. Its distinctive olive-green color is due to its iron content.
- Zircon: A zirconium silicate (ZrSiO4), zircon is one of the hardest natural gemstones, with a hardness of 7.5. It is also known for its high refractive index, which gives it a brilliant sparkle.
Organic and Non-Crystalline Gems
- Pearl: Unlike most gemstones, pearls are organic, formed within the soft tissue of a living mollusk. They are composed primarily of calcium carbonate (aragonite or calcite) and conchiolin. Pearls have a hardness of only 2.5 to 4.5 on the Mohs scale, making them relatively soft and requiring careful handling.
- Opal: Opal is unique because it is amorphous, meaning it lacks a crystalline structure. It is composed of hydrated silica (SiO2·nH2O) and contains a significant amount of water. Its hardness is typically between 5.5 and 6.5. The famous play-of-color is caused by the diffraction of light through a network of microscopic silica spheres within the stone.
- Turquoise: An opaque mineral composed of hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O), turquoise has a hardness of 5 to 6. Its characteristic blue-to-green color is derived from its copper content.
| Gemstone | Mineral Group/Type | Chemical Composition | Mohs Hardness |
|---|---|---|---|
| Garnet | Silicate | X3Y2(SiO4)3 | 6.5 - 7.5 |
| Amethyst | Silicate (Quartz) | SiO2 | 7 |
| Diamond | Native Element (Carbon) | C | 10 |
| Emerald | Silicate (Beryl) | Be3Al2(SiO3)6 | 7.5 - 8 |
| Ruby/Sapphire | Silicate (Corundum) | Al2O3 | 9 |
| Peridot | Silicate (Olivine) | (Mg,Fe)2SiO4 | 6.5 - 7 |
| Opal | Amorphous Silica | SiO2·nH2O | 5.5 - 6.5 |
| Turquoise | Phosphate | CuAl6(PO4)4(OH)8·4H2O | 5 - 6 |
Metaphysical Beliefs and Symbolism
Throughout history, gemstones have been imbued with symbolic meanings and believed to possess metaphysical properties. While these beliefs are part of cultural lore rather than scientific fact, they contribute significantly to the enduring appeal of birthstones.
- Garnet is widely regarded as a stone of protection, believed to ward off negative energy and bring strength and courage to its wearer.
- Amethyst has long been associated with tranquility and clarity of mind. It is often used in meditation to promote spiritual awareness and is thought to have a calming effect.
- Aquamarine is known as the "stone of courage." Sailors historically wore it for safe passage across stormy seas, believing it would ensure a safe journey and calm the waves.
- Diamond is the ultimate symbol of eternal love, purity, and innocence. Its unmatched strength is also believed to represent invincibility.
- Emerald is traditionally associated with rebirth, fertility, and love. It is believed to bring prosperity and vitality, and to enhance intuition and insight.
- Ruby is considered the "king of gems" and is linked to passion, power, and vitality. It was thought to protect its wearer from harm and to stimulate the heart chakra.
- Peridot is believed to be a stone of compassion. It has been used throughout history to ward off evil spirits and to protect against nightmares.
- Sapphire is a stone of wisdom and truth. It is associated with focus, clarity, and spiritual enlightenment, and was believed to protect against envy and harm.
- Opal is a stone of inspiration and creativity. Its shifting colors are thought to reflect the moods and emotions of its wearer, enhancing self-expression.
- Tourmaline is known as a "psychic sponge," believed to absorb negative energy and transform it into positive vibrations. Different colors are associated with different properties.
- Topaz is associated with joy, generosity, and abundance. It is believed to soothe tempers and calm emotions.
- Citrine is known as the "merchant's stone" for its supposed ability to attract wealth and prosperity. It is also linked to personal clarity and cleansing.
- Tanzanite is a relatively new stone in the world of lore, but it is associated with transformation and higher consciousness.
- Turquoise is one of the oldest known protective stones, believed to bring good fortune, health, and safety. It was often used in amulets and talismans.
- Zircon is believed to aid in sleep, ward off nightmares, and promote honor and purity.
Care and Cleaning of Birthstone Jewelry
The durability of a birthstone, primarily determined by its hardness and cleavage, dictates the proper methods for its care and cleaning.
- Hard Stones (Mohs 8-10): Diamonds, sapphires, and rubies are exceptionally durable and can be cleaned with warm water, a mild soap, and a soft brush. They are resistant to scratching by most other materials.
- Moderately Hard Stones (Mohs 7-7.5): Amethyst, garnet, aquamarine, topaz, and spinel are relatively tough but can still be damaged by hard blows. They are safe to clean with warm soapy water and a soft brush. Avoid harsh chemicals and ultrasonic cleaners if the stone has fractures.
- Softer Stones (Mohs 6-7): Peridot, tourmaline, and zircon require more care. They can be cleaned with a soft brush and mild soap, but avoid sudden temperature changes and harsh chemicals. Zircon, in particular, can be brittle.
- Delicate and Organic Stones (Mohs below 6): Opal, turquoise, and pearl demand gentle handling. They should be wiped with a soft, damp cloth. Avoid ultrasonic cleaners, steam, and harsh chemicals, as these can damage or discolor them. Pearls are particularly susceptible to acids, cosmetics, and perfumes, which can dull their luster.
Conclusion
The twelve birthstones offer a remarkable journey through geological time, human history, and cultural expression. From the deep reds of garnet and ruby to the tranquil blues of aquamarine and sapphire, each gem provides a unique window into the planet's formation and our enduring fascination with its treasures. While modern lists provide a convenient guide, the tradition is rooted in centuries of lore and belief, adding a layer of personal meaning that transcends mere aesthetics. By understanding the origins, properties, and care of these monthly gems, enthusiasts and collectors can make informed choices and develop a deeper appreciation for the birthstone they choose to wear.