Birthstones for May and June
If there is one gemstone that has been in demand since millennia and captures the attention of royals, connoisseurs and commoners alike, it is the evergreen emerald. The May-born must therefore consider themselves lucky as their birthstone’s fame is undisputed. Considered to bestow good luck on its wearers, emerald, the lively green gemstone that symbolises new life, is also believed to cure ailments and bring peace.Considered priceless, emeralds denote faith, love and friendship. Pearls are associated with the month of June and are linked to purity and chastity.
The natural gems have found mention in almost all cultures and are held in high esteem. It is believed that Lord Krishna, who discovered the first pearl, presented it to his daughter at the time of her wedding. Likewise, Christians, too, associate this lustrous gem with brides and weddings. Islam upholds pearls as the symbol of perfection.
The Gemological Institute of America (GIA), known as the world’s foremost authority in gemmology, gives you insights into these wondrous gemstones.
Emerald: The Garden Green Treasure
Did You Know?
Cherished by Spanish conquistadors, Inca kings, Mughals and pharaohs, emerald has been prized for thousands of years as the gem most associated with lush landscapes and rich greens. Its colour reflects new spring growth, which makes it the perfect birthstone choice for the month of May.
Emerald is the standard by which all other green gemstones are measured. Chromium, vanadium and iron are the trace elements that cause emerald’s colour. The presence or absence of each, and their relative amounts, determine the exact colour of an emerald crystal. Subtle variations in colour can make significant differences in the value of the gem.
Mined in many countries throughout the world, emerald is the green to greenish blue variety of beryl, a mineral species that includes aquamarine and other colours of beryl. Most gem experts say a stone is green beryl when the colour is “too light” for it to be classified as emerald. They often differ, however, on the degree of green that makes one stone an emerald and another less expensive green beryl.
History and Lore
Emerald’s name comes from the ancient Greek word for green, “smaragdus.” The first known emerald mines were in Egypt – Cleopatra was credited to have a passion for emerald, and used it in her royal adornments. It is believed that these mines were worked as early as 3500bc.
Legend says emerald has the power to make its wearer more intelligent and quick-witted. It was once believed to cure diseases like cholera and malaria.
The 4C’s: Clarity, Colour, Cut and Carat Weight
An emerald cross and gold rosary recovered from the Nuestra Señora de Atocha shipwreck. The “El Castillo,” left, is a 442-carat emerald crystal from the Cosquez mine, Muzo, Colombia, and “Angel of the Andes,” right, is a 982-carat emerald crystal from Chivor, Colombia. The four emerald crystals in the foreground from La Pita Mine in Muzo, Colombia, range in size from 70 to 150 carats. Large crystals courtesy of Roz and Gene Meieran; small crystals courtesy of Ron Ringsrud and Hernando Sanchez, Perfect Emerald, Ltd. Bogotá, Colombia; Cross courtesy of Eileen Weatherbee. © Robert Weldon/GIA
The most desirable emerald colours are bluish green to pure green, with vivid colour saturation and tone that’s not too dark. The most-prized emeralds are highly transparent, their colour is evenly distributed and there is no eye-visible colour zoning.
If the hue is too yellowish or too bluish, the stone is not emerald, but a different variety of beryl, and its value drops accordingly.
Emeralds typically contain inclusions that are visible to the unaided eye. Emerald inclusions are often described as looking mossy or garden-like. They’re sometimes called “jardin”, which is French for garden. Jewellers, others in the gem trade and some consumers understand and accept the presence of inclusions in emeralds. But when the inclusions have a negative effect on transparency and clarity, they also dramatically reduce value. Emeralds that do not have visible inclusions are especially valuable because they’re very rare.
Due to the crystal shape, emeralds are commonly fashioned using a rectangular step cut called ‘emerald cut’. Nearly all emerald crystals have significant fractures (sometimes called fissures in the trade) that make them difficult to cut. Well-cut stones maximize the beauty of the colour and minimize the impact of fissures to create a bright, lively stone.
Emeralds come in a wide range of sizes. Some emeralds in museums and private collections weigh hundreds of carats, while others weigh fractions of a carat. If the colour, clarity and cut for two emeralds are the same, the price can rise dramatically as the size increases.
Surface-reaching fractures in emerald are commonly filled with oils, waxes or artificial resins to reduce the visibility of the fractures and improve the apparent clarity. These substances have varying degrees of stability in treated emeralds. Gemmological tests can reveal if an emerald has been treated.
How to Care for Emerald
Emerald is 7.5 to8 on the Mohs hardness scale and requires more care in wearing than ruby or sapphire.Most emeralds are treated to reduce the appearance of fractures and can be damaged by ultrasonic or steam cleaning. Warm soapy water is a safe cleaning method for emerald.
Did You Know?
Pearls are for those who have refined tastes. The birthstone for June-born, pearls – natural and cultured – occur in a wide variety of colours. The most familiar are white and cream, but the palette extends to every hue. These organic gems are created inside a living mollusc – often an oyster – beneath the water’s surface. Pearls are made up of layers of calcium carbonate most popularly in the form of nacre, a natural substance produced by pearl oysters that coats the inside of the animal’s shell. This beautiful, lustrous nacre is the very essence of a pearl. Natural pearls form around a microscopic irritant without human help of any kind, while cultured pearls require human intervention and care. There are four major types of cultured pearls: Akoya, South Sea, Tahitian and freshwater.
History and Lore
People have coveted pearls as symbols of wealth and status for thousands of years. A Chinese historian recorded the oldest written mention of natural pearls in 2206bc. The first steps towards pearl culturing began hundreds of years ago in China; Japanese pioneers successfully produced whole cultured pearls at the beginning of the 20th century. These became commercially important in the 1920s when natural pearl production began to decline.
The spherical shape of some pearls has led many cultures to associate this gem with the moon. In ancient China, pearls were believed to guarantee protection from fire and firebreathing dragons.
The GIA 7-Pearl Value Factors
The qualities that determine the overall value of a natural or cultured pearl or a piece of pearl jewellery are size, shape, colour, lustre, surface quality, nacre quality and – for jewellery with two or more pearls – matching.
A larger pearl (measured in millimetres) is typically more valued. But a pearl’s ultimate worth depends on how it combines the complete mix of value factors. Cultured pearls range from 2-16mm in diameter.
While round is the most familiar shape, pearls come in many surprising forms. Some resemble teardrops, crosses, coins and other recognizable shapes. A pearl that is wellshaped or symmetrical will be more valuable than one that’s irregular.
The dominant colour, known as body colour, is often modified by additional colours called overtones, which are typically pink (sometimes called rose), green, purple or blue. Some pearls also show the iridescent phenomenon known as orient. A pearl’s colour is a combination of its body colour, overtone and orient. Cultured pearls display a broad palette of subtle hues, ranging from warm (yellow, orange and pink) to cool (blue, green and violet).
Lustre : The intensity of light reflected from or just below the surface of the pearl is called lustre.It is caused by light travelling through translucent layers of nacre – and reflecting back to the eye from deep within the pearl. Pearls with high lustre have sharp bright reflections on the surface.
The number, nature and location of surface characteristics (abrasions, bumps, chips and cracks) can affect the value of a pearl. Numerous or severe surface irregularities – such as chips or gaps – can threaten the durability and cause it to break or peel.
Lustre and nacre quality are closely related. If the nucleus is visible under the nacre, or if the pearl has a dull, chalky appearance, you can assume that the nacre is thin. This affects the lustre as well as the durability of the pearl. Nacre thickness is evaluated to make sure that cultured pearls are durable as well as beautiful.
Jewellery designers sometimes deliberately mix colours, shapes and sizes for unique effects, but for most jewellery the pearls should match.
Some pearls are dyed or bleached to improve colour. These treatments can change in appearance over time.
How to Care for Pearl
Pearls rank 2.5 on the Mohs hardness scale, which means they’re very soft and can be easily damaged. Perfume, make-up and hairspray contain ingredients that can eat away the nacre of pearls and cause permanent dulling. The best way to clean pearls is with a soft damp cloth each time after you wear them. Pearls need a certain amount of moisture to retain their beauty. Avoid storing pearls in an airtight or overly dry environment.