Birthstones are gemstones associated with each month of the year, believed to hold symbolic meaning and power for individuals born in that month. This tradition, which spans centuries, connects modern jewelry and personal adornment to ancient history, theology, and folklore. The concept is widely believed to have originated from the biblical breastplate of Aaron, a high priest in the Hebrew Bible, which was adorned with twelve gemstones representing the twelve tribes of Israel. Over time, this religious symbolism evolved into a secular practice of associating specific stones with the twelve months, gaining widespread popularity in the 18th and 19th centuries. Today, birthstones serve as meaningful gifts and personal talismans, with each gem offering a unique blend of color, history, and attributed properties.
The modern birthstone list, largely standardized in the United States in 1912 by the National Association of Jewelers, includes a primary gemstone for each month. However, many months also have traditional or alternative stones that remain popular due to historical significance, availability, or cost. This guide explores each of the twelve months, detailing their associated gemstones, historical origins, gemological properties, and cultural significance, drawing from established historical accounts and gemological references.
History and Lore: From the Breastplate of Aaron to Modern Lists
The foundational story of birthstones begins in the first century with the historian Flavius Josephus. While studying the Book of Exodus, Josephus noted that the breastplate of Aaron, the first High Priest, was set with twelve distinct stones. He proposed that these stones could represent not only the twelve tribes of Israel but also the twelve months of the year and the twelve signs of the zodiac. The stones listed in Exodus—raw carnelian, chrysolite, emerald, turquoise, sapphire, amethyst, jacinth, agate, crystal (quartz), raw beryl, lapis lazuli, and jasper—were chosen for their symbolic significance, though their exact identities are debated due to ancient naming conventions based on color rather than chemical composition. For example, what was called "sapphire" in ancient times is now believed to be lapis lazuli, and "emerald" could have been misidentified peridot.
This early association between stones and months laid the groundwork for a tradition that continued through the centuries. By the 18th century in Poland, it became customary to own a set of twelve gemstones and wear the one corresponding to the current month. The modern system, however, was formalized to address the scarcity and high cost of certain traditional gems. In 1912, the National Association of Jewelers in the United States established an official list, which was later updated by organizations like the American Gem Trade Association (AGTA). This list prioritized gems that were more accessible and affordable, introducing modern alternatives like tourmaline for October and citrine for November. Today, consumers freely mix modern and traditional options, often selecting stones based on personal preference, budget, or aesthetic appeal rather than strict adherence to a single list.
January: Garnet
Modern Birthstone: Garnet Traditional Birthstone: Garnet
Garnet is the birthstone for January, a gemstone renowned for its deep, rich red hues, though it occurs in a surprisingly wide range of colors. The name "garnet" is derived from the French word grenate, meaning "seedy," due to its resemblance to the seeds of a pomegranate. Historically, garnet has been a symbol of constancy and protection. It was often believed to keep the wearer safe during travel, a belief rooted in its reputation for warding off danger.
From a geological perspective, garnet is not a single mineral but a group of silicate minerals with similar crystal structures but varying chemical compositions. The most common species include pyrope (typically red), almandine (red to violet-red), spessartine (orange to reddish-brown), grossular (various colors including green and yellow), andradite (yellow to green), and uvarovite (green). The Mohs hardness of garnet ranges from 6.5 to 7.5, making it a reasonably tough gemstone suitable for various jewelry applications, including rings and bracelets. While most garnet species are not considered rare, certain varieties, such as the blue garnets discovered in the 1990s, are exceptionally uncommon. Garnet is mined in several countries, including Sri Lanka, India, Brazil, and the United States.
February: Amethyst
Modern Birthstone: Amethyst Traditional Birthstone: Amethyst
Amethyst, a variety of quartz, is the birthstone for February. Its distinctive purple color, ranging from light lavender to deep violet, has made it a favorite for centuries. Amethyst is associated with sincerity, peace, and spiritual awareness. It is also believed to strengthen relationships and give its wearer courage. In the past, amethyst was considered as valuable as ruby and emerald, and it was once reserved exclusively for royalty. Today, it is more widely available, making it an accessible and popular choice for jewelry.
Amethyst is composed of silicon dioxide (SiO₂) and gets its purple color from trace amounts of iron and natural irradiation. It has a Mohs hardness of 7, making it durable enough for everyday wear. Major sources of amethyst include Brazil, Uruguay, and Zambia. The February birthstone is also linked to the idea of transformation and intuition, aligning with its calming and meditative properties.
March: Aquamarine and Bloodstone
Modern Birthstone: Aquamarine Traditional Birthstone: Bloodstone
March is represented by two distinct gemstones: aquamarine (modern) and bloodstone (traditional). Aquamarine, from the beryl family, is prized for its serene blue to blue-green color, reminiscent of the sea. Its name comes from the Latin words aqua (water) and marina (sea). Aquamarine is associated with wisdom, clarity, and calm. It is said to help with communication and reduce stress.
Aquamarine is a beryllium aluminum silicate (Be₃Al₂(SiO₃)₆) with a Mohs hardness of 7.5 to 8, making it an excellent choice for jewelry. It is often heat-treated to enhance its blue color. Major mining locations include Brazil, Nigeria, Madagascar, Pakistan, and Mozambique.
The traditional March birthstone, bloodstone, is a dark green chalcedony (a variety of quartz) with red iron oxide inclusions, which were thought to resemble drops of blood. Historically, it was known as the "martyr's stone" and was associated with courage and vitality. Bloodstone has a Mohs hardness of 6.5 to 7 and is found in India, Brazil, Australia, and the United States.
April: Diamond
Modern Birthstone: Diamond Traditional Birthstone: Diamond
Diamond is the birthstone for both modern and traditional lists for April. It is the hardest known natural material, with a Mohs hardness of 10, and is composed of pure carbon in a crystal structure. Diamonds are symbols of innocence, purity, and eternal love, making them the quintessential choice for engagement rings.
The word "diamond" comes from the Greek adamas, meaning "invincible," reflecting its unmatched durability. While colorless diamonds are most famous, they can occur in various colors, including yellow, brown, blue, and pink, depending on trace elements and structural defects. Major diamond sources include Russia, Botswana, Canada, and South Africa. Historically, diamonds were believed to have healing properties and were worn as talismans for protection.
May: Emerald
Modern Birthstone: Emerald Traditional Birthstone: Emerald
Emerald, a variety of the mineral beryl, is the birthstone for May. Its vibrant green color, caused by trace amounts of chromium and sometimes vanadium, has made it one of the most coveted gemstones for millennia. Emerald is associated with happiness, rebirth, and foresight.
Emerald is a beryllium aluminum silicate (Be₃Al₂(SiO₃)₆) with a Mohs hardness of 7.5 to 8. However, it often contains inclusions (internal features) and fractures, known as jardin (French for "garden"), which are accepted as part of its character. These inclusions make emeralds more brittle than other beryls, requiring careful handling. The finest emeralds come from Colombia, but significant sources also include Zambia, Brazil, and Zimbabwe. Emeralds have been treasured since ancient Egypt, where they were mined as early as 1500 BCE, and are linked to the goddess Venus.
June: Pearl and Alexandrite
Modern Birthstone: Alexandrite Traditional Birthstone: Pearl
June offers a choice between the organic pearl (traditional) and the color-changing alexandrite (modern). Pearls are unique among birthstones as they are created by living organisms—oysters and mussels—rather than geological processes. They are formed when an irritant is coated with layers of nacre, resulting in a lustrous gem. Pearls symbolize purity, wisdom, and wealth. They have a Mohs hardness of 2.5 to 4.5, making them relatively soft and requiring careful protection from scratches and chemicals. Pearls are primarily cultured today, with major production in China, Japan, and French Polynesia.
Alexandrite, a variety of chrysoberyl, is renowned for its dramatic color change—from green in daylight to red or purple under incandescent light. Discovered in Russia's Ural Mountains in 1830 and named after Tsar Alexander II, it symbolizes good fortune and balance. Alexandrite is composed of beryllium aluminum oxide (BeAl₂O₄) and has a high Mohs hardness of 8.5, making it durable. It is now mined in Brazil, Sri Lanka, and East Africa. The gem's rarity and unique property have made it highly prized.
July: Ruby
Modern Birthstone: Ruby Traditional Birthstone: Ruby
Ruby, a variety of the mineral corundum, is the birthstone for July. Its vivid red color, caused by chromium, has made it a symbol of passion, vitality, and freedom. The name "ruby" comes from the Latin rubeus, meaning red. Historically, rubies were considered the "king of gems" and were believed to bring good fortune and protection.
Ruby is an aluminum oxide (Al₂O₃) with a Mohs hardness of 9, second only to diamond, making it exceptionally durable for jewelry. The finest rubies, known as "pigeon's blood," come from Myanmar (Burma), but significant sources also include Thailand, Mozambique, and Madagascar. Rubies have been mined for over 2,500 years, with early records from Sri Lanka and India. Their value is often determined by color intensity, with the most prized rubies exhibiting a vivid, saturated red with a slight blue undertone.
August: Peridot and Spinel
Modern Birthstone: Peridot (with Spinel as an alternative) Traditional Birthstone: Sardonyx
August's primary modern birthstone is peridot, a gemstone with a distinctive olive-green color. Peridot is one of the few gemstones that occurs in only one color family, though it can vary from yellow-green to brownish-green. It is associated with friendship and is believed to ward off nightmares and evil spirits. Peridot is the gem variety of olivine, an iron magnesium silicate (Mg,Fe)₂SiO₄, with a Mohs hardness of 6.5 to 7. It is found in volcanic rock and alluvial deposits. Major sources include Pakistan, the United States (Arizona), and Myanmar.
Spinel is also recognized as an alternative modern birthstone for August. Historically, spinel was often mistaken for ruby, including the famous "Black Prince's Ruby" in the British Crown Jewels, which is actually a red spinel. Spinel comes in a variety of colors, including red, pink, blue, and black, and is composed of magnesium aluminum oxide (MgAl₂O₄) with a Mohs hardness of 8. It is mined in Myanmar, Sri Lanka, and Tajikistan.
The traditional birthstone for August is sardonyx, a banded variety of chalcedony (quartz) with alternating layers of sard and onyx. It was historically used for cameos and intaglios and is associated with courage and protection.
September: Sapphire
Modern Birthstone: Sapphire Traditional Birthstone: Sapphire
Sapphire, another variety of corundum, is the birthstone for September. While most famous for its deep blue color, sapphire occurs in every hue except red (which is classified as ruby). Sapphires symbolize truth, wisdom, and nobility. The blue color comes from trace amounts of titanium and iron.
Sapphire has a Mohs hardness of 9, making it extremely durable. The most valued blue sapphires come from Kashmir, Sri Lanka, and Myanmar, but sources also include Australia, Thailand, and Montana, USA. Sapphires have been worn by royalty and clergy for centuries, believed to protect against envy and harm. Padparadscha sapphires, a rare pink-orange variety, are particularly prized.
October: Tourmaline and Opal
Modern Birthstone: Tourmaline Traditional Birthstone: Opal
October is represented by two beautiful gemstones: tourmaline (modern) and opal (traditional). Tourmaline is known for its incredible color range, earning it the name "rainbow gemstone." It can be found in pink, green, blue, yellow, and even black. Tourmaline is associated with hope and inspiration. It is a complex borosilicate mineral with a Mohs hardness of 7 to 7.5. Major sources include Brazil, Afghanistan, and the United States (Maine and California).
Opal is an amorphous form of silica, prized for its play-of-color—the iridescent flash of light that moves across the stone as it is rotated. Opal symbolizes hope, purity, and creativity. It has a Mohs hardness of 5.5 to 6.5, making it relatively soft and prone to cracking, requiring careful handling. Opals are primarily mined in Australia, which produces most of the world's supply.
November: Topaz and Citrine
Modern Birthstone: Citrine (with Topaz as an alternative) Traditional Birthstone: Topaz
November's modern birthstone is citrine, a variety of quartz known for its warm yellow to orange-brown hues. Citrine is associated with loyalty and is believed to carry the warmth of the sun, promoting vitality and energy. It is often called the "merchant's stone" for its supposed ability to attract wealth. Citrine is composed of silicon dioxide (SiO₂) and has a Mohs hardness of 7. Much of the citrine on the market is heat-treated amethyst. Major sources include Brazil, Uruguay, and Bolivia.
Topaz is the traditional birthstone for November and is also an alternative modern stone. Topaz is a silicate mineral containing fluorine and aluminum, with a Mohs hardness of 8. It occurs in a variety of colors, including blue, yellow, pink, and clear. The most famous topaz is the Imperial Topaz, a rich orange-pink variety. Topaz is mined in Brazil, Nigeria, and Sri Lanka. Historically, topaz was believed to have cooling properties and could prevent madness.
December: Tanzanite, Blue Zircon, Blue Topaz, Turquoise, and Lapis Lazuli
Modern Birthstones: Tanzanite, Blue Zircon, Blue Topaz Traditional Birthstones: Turquoise, Lapis Lazuli
December has the most birthstone options, reflecting its status as a month of celebration and gifting. The modern stones include tanzanite, blue zircon, and blue topaz, while traditional stones are turquoise and lapis lazuli. All these stones share blue hues, symbolizing success, wisdom, and tranquility.
Tanzanite, a variety of zoisite, was discovered in Tanzania in the 1960s and is known for its vivid violet-blue color. It has a Mohs hardness of 6.5 to 7 and is often heat-treated to enhance its color. Blue zircon is a natural gemstone (not to be confused with synthetic cubic zirconia) with a high refractive index and brilliance. It has a Mohs hardness of 6.5 to 7.5 and is mined in Cambodia, Sri Lanka, and Myanmar. Blue topaz, a treated variety of topaz, is widely available and affordable, with a Mohs hardness of 8.
The traditional stones are turquoise and lapis lazuli. Turquoise is an opaque blue-green mineral, a hydrous phosphate of copper and aluminum, with a Mohs hardness of 5 to 6. It has been mined for over 5,000 years, with notable sources in Iran and the southwestern United States. Lapis lazuli is a rock composed mainly of lazurite, calcite, and pyrite, known for its deep blue color with gold flecks. It has a Mohs hardness of 5 to 5.5 and has been used since antiquity, including in the burial mask of Tutankhamun.
Care and Cleaning
Proper care for birthstones depends on their hardness, cleavage, and chemical stability. As a general rule, gems with a Mohs hardness below 7 should be protected from scratches and stored separately from harder stones. Always remove jewelry before engaging in physical activities or using harsh chemicals.
- Hard Stones (Mohs 8-10): Diamond, sapphire, ruby, alexandrite, and topaz can be cleaned with warm soapy water and a soft brush. Avoid steam cleaners for treated stones.
- Medium-Hard Stones (Mohs 7-7.5): Amethyst, garnet, aquamarine, and peridot are durable but should be cleaned gently. Avoid sudden temperature changes.
- Softer Stones (Mohs 5.5-6.5): Opal, turquoise, lapis lazuli, and pearls require extra care. Clean with a damp cloth only; avoid ultrasonic cleaners and chemicals. Pearls are especially sensitive to acids, perfumes, and perspiration.
- Organic and Treated Stones: Pearls and organic gems should be wiped clean after wear. Heat-treated stones like tanzanite and citrine may be sensitive to heat and should be handled with care.
Conclusion
The twelve birthstones offer a fascinating intersection of geology, history, and culture. From the ancient breastplate of Aaron to the modern jewelry market, these gems have evolved in meaning and accessibility while retaining their symbolic power. Each stone tells a story—whether it's the protective garnet of January, the regal ruby of July, or the diverse options of December. For enthusiasts, buyers, and students alike, understanding the properties and lore behind these gems enriches the experience of choosing and wearing birthstone jewelry. As the tradition continues to adapt, birthstones remain a timeless way to celebrate personal identity and connect with a legacy that spans millennia.