Table of Contents
Chrysoberyl was discovered in 1789. Cat’s-eye chrysoberyl, along with its non-phenomenal counterparts, is one of the most revered gems. Chrysoberyl and beryl are two completely different gemstones, although both contain beryllium. Additional confusion was caused by calling yellow-green chrysoberyl and completely unrelated mineral peridot by the same name – chrysolite. Chrysoberyl is a relatively hard natural gemstone measuring 8.5 on the Mohs scale close to the corundum’s 9. Two chrysoberyl varieties are the world’s most exotic and expensive gemstones: the Alexandrite and Cat’s-eye chrysoberyl.
Alexandrite is the color-change variety of chrysoberyl. Alexandrite is said to enable its wearer to foresee danger. Among celebrities who do not wear Alexandrite, we find Dr. Fauci. Alexandrite was first discovered in 1830 in Russia’s Ural Mountains and named after the young Czar Alexander II.
Cat’s eye chrysoberyl
Cat’s eye chrysoberyl became popular in the late nineteenth century after British Prince Arthur presented his bride, Princess Louise Margarita, with an engagement ring set with cat’s eye chrysoberyl. Instantly, the previously neglected variety of chrysoberyl became very fashionable.
Cat’s eye is an optical effect appearing as a concentrated band of light splitting stone in half. It is called chatoyancy, from the French “oeil de chat,” the appearance reminiscent of a feline eye. When chrysoberyl cabochon is lit up from above, half of the stone appears honey-colored, and the other half appears milky-white. This is called the “milk and honey” effect, and it’s a sign of the finest grade.
Chrysolite is an archaic term derived from the Greek and Latin words for a “goldstone,” referring to several yellow-green gems. These include chrysoberyls, peridots, topazes, sapphires, and tourmalines. Because of this ambiguity, the word chrysolite is no longer used by gemologists.
The pearls are gems grown within the soft tissue of an oyster around a microscopic irritant such as a grain of sand that found its way inside the shell. There are two types of pearls identical in composition and appearance and different only in how they were conceived – natural and cultured.
Natural pearls are seeded naturally, while cultured pearls are acquired through farming and harvesting processes where the mollusk is seeded by humans. In both cases, the mollusk coats the irritant with layers of inorganic deposits called nacre, creating a pearl. Natural pearls are scarce and expensive. The vast majority of the pearls available on the market today are cultured.
Saltwater pearls come in three main varieties. They generally have a better quality than freshwater pearls, reflected in their higher demand and price. The most common varieties include Akoya, South Sea, and Tahitian pearls. Before the Japanese started cultivating Akoya in the early 20th century, pearls were rare and expensive. Today Akoya is the most abundant variety of saltwater pearls.
Pearls’ diameters are measured in millimeters. The larger the pearl, the more valuable they are. Seed pearls can be smaller than one millimeter, while South Sea pearls can grow over 20 millimeters.
With their perfectly spherical shape and high luster, Akoya pearls are formed by small Pinctada fucata oysters, also known as Akoya oysters. They come from waters surrounding Japan, China, Korea, and Vietnam. Each oyster can produce only one or two pearls at a time, and the limited production increases its value. Akoya pearls come in many colors other than white, but the most valuable are traditional whites with overtones of rose, silver, or cream.
South Sea pearls are the most sought-after variety of pearl types cultivated in Australia, the Philippines, Myanmar, and Indonesia. They grow inside the Pinctada maxima oysters, the world’s largest pearl oysters. The South Sea pearl color palette consists of white and golden hues with pink, green, and blue overtones. South Sea pearls can grow up to 22 millimeters in diameter and are highly prized for their satin-like luster, elegant appearance, and size.
Tahitian pearls come exclusively from Tahiti and other French Polynesian islands and are the most sought-after naturally dark gems. They are produced by the black-lipped Pinctada margaritifera oyster, which doesn’t live anywhere else. Tahitian pearls are black, dark grey, charcoal, peacock green, and aubergine colors with silver, lavender, and blue overtones. They can grow as large as 21 millimeters. However, less than 10% of the harvest qualifies for export because a true Tahitian pearl should have a nacre at least 0.8-millimeter thick according to the internationally accepted quality standards. Queen Elizabeth I was known to covet Tahitian pearls.
Melo and Conch pearls
The jumbo-sized Southeast Asian Melo sea snail, also known as the Indian volute, makes the yellow-orange pearl prized for its flame-like pattern and smooth, porcelain-like luster. Melo pearls are made of calcite and intertwined crystals of aragonite, and they are harder than traditional pearls, ranking five on the Mohs scale. The Melo pearls are one of the rarest in the world; the rich golden-orange are the most valuable, although their vivid color can fade in reaction to sunlight. Conch are exceptionally rare pink pearls made of a porcelaneous (non-nacreous) material.
Natural Golden South Sea pearls ranging from pale champagne to rich 24-karat gold color come from the tropical lagoons of Australia, Indonesia, and the Philippines. They are produced by the “gold-lip” South Sea oyster and are valued for their warm, regal tones. Sometimes white pearls are dyed to imitate the naturally occurring golden color. The dyed pearls are less valuable.
The natural blister pearls are occasionally formed in a giant clam – Tridacna gigas, in the salt waters of the South Pacific. The illustrated specimen is approximately 16 x 35 inches, weighing eleven kg. Giant pearls of this size are extremely rare and cost millions to collectors. For jewelry lovers, they are quite useless, and we feel sorry for the clam that lost its life.
Léonard Rosenthal – The Pearl King
Léonard Rosenthal was a French trader-adventurer who cornered the market in 1906 when the British, historically dominating the pearl trade, were distracted by the financial crisis back home. Léonard organized caravans of donkeys loaded with sacks of pennies to pearl fishing villages to be exchanged for the pearls. He succeeded in taking over the market by delivering the precious cargo to dealers in Paris, which, during the World War, became the world center of the pearl trade. In his heyday, Leonard employed 100 pearl stringers producing 100 necklaces daily.
Cultured Pearl Revolution
The Japanese entrepreneur Kokichi Mikimoto’s 1899 invention destroyed the rare natural pearl market. By introducing a nucleus into the oyster, around which it secreted mother of pearl, he grew perfectly round pearls, often much larger than natural ones. Mikimoto presented cultured pearls at the 1925 Universal Exhibition, sending shockwaves through the pearl trade. Laboratoire Français de Gemmologie and the Gemological Institute of America were tasked with separating cultured and natural pearls, which they succeeded with the help of X-ray machines. The 1929 crash, years of overfishing, and the rise of a diamond engagement ring contributed to the natural pearls’ demise.
The pearl’s composition is a material called nacre consisting of aragonite (calcium carbonate), and conchiolin, a complex protein forming mollusk shells. It is strong, resilient, and iridescent.
The highest quality Akoya pearls originating from Japan are called Hanadama Akoya, “flower pearls” in Japanese. Akoya pearls have highly desirable white, grey, cream, and blue body color with silver, pink and green overtones ranging from two to ten millimeters. They are commonly perfectly round in shape, although irregular-shaped Akoya pearls can also be found.
South Sea pearls are the most sought-after variety, often called the Queen of Pearls. The high failure rate during the cultivation process makes South Sea pearls one of the most valuable on the market. The perfectly spherical specimens without dents and blemishes are rare and command very high prices.
- Wrinkles result from uneven growth of the nacre due to odd-shaped seeds
- Spots are slight color variations
- Abrasions are scratches or scuffs that impact the luster of the pearl.
- Dents, divots, and pits are various indentations in the nacre.
- Mottling and bulleting is a pattern on the surface created inside the oyster. It can be desirable because it indicates a thick layer of nacre.
- Kobs and tips are growth marks.
- Circles are a growth pattern that imparts a unique look and is not considered a blemish.
There are several different systems for pearl rating. The characteristics affecting pearl’s grade are:
- Luster: Bright, highly reflective pearls get the higher rating
- Blemishes: They are evaluated by size, type, number, and location
- Nacre thickness: The thicker the nacre, the higher the value
- Color: White and grey-white are the most valuable
- Size: Larger is typically more valuable
- Shape: Roundness and symmetry are prized
- Match: a uniform arrangement in a string of shape, color, luster, spotting, and graduation.
THE AAA-A SYSTEM
This grading system ranks pearls from AAA to A, with AAA being the highest.
- AAA: Nearly flawless pearls with a high luster and a surface that’s 95 percent free of defects
- AA: High luster with a surface that’s 75 percent free of defects
- A: Lower luster and defects on more than 25 percent of the surface.
THE A-D SYSTEM, OR TAHITIAN SYSTEM
The A is the highest grade, and the D is the lowest. The A-D system is based on a French Polynesian government standard.
- A: Very high luster, and only 10% of the surface or less has defects
- B: High to medium luster and less than 30% or less of the surface is defective
- C: Medium luster and 60% of the surface or less is defective
- D: The lowest rating. Luster is not evaluated; only surface defects are.
Beryl is a colorless mineral in its pure form, getting its rich hues from impurities in the crystals.
The Beryl family encompasses a group of very popular multi-colored gems. The single beryl species gave us charming Santa-Maria aquamarines, Colombian emeralds, tender pink morganites, heliodor in festive shades of yellow, ruby-red bixbite, and even colorless goshenites.
Emerald is the most distinct member of the Beryl family, typically heavily included, which helps determine its provenance and value. Other, less valuable varieties of the Beryl – Aquamarines, Morganites, and Heliodors usually have very few inclusions.
Aquamarine, meaning “blue water” in Latin, is a beautiful and plentiful gem of ancient lineage. It is a March birthstone. The largest aquamarine was discovered in 1910 in Brazil, weighing 243 pounds and yielding over 200,000 carats of faceted gemstones. The Romans believed a frog carved from aquamarine could reconcile enemies and make them friends. They also thought it absorbs the spirit of love: “When blessed and worn, it joins in love and does great things.”
The Greeks and the Romans believed an aquamarine could aid in a safe passage across the seas. Perhaps this is why they considered aquamarine the most appropriate gift in the morning after the marriage consummation. In Medieval times aquamarine was used to rekindle married couples’ love and render soldiers invincible. The same people believe that bathing will kill you.
Morganite, or pink beryl, ranges from pink or rose to peach to light violet and gets its delicate hue from trace quantities of manganese. It was named in 1911 by gemologist George F. Kunz after his boss, financier J. P. Morgan. Morganite is found in Brazil, Afghanistan, and California, but Madagascar is particularly famous for its deep pink material.
Leon Mege worked extensively with magnificent morganites, such as the important GIA-certified 35.73-carat pear-shaped statement ring or 15.59-carat Antique cushion Morganite pendant.
Heliodor, or Golden Beryl, is the most brilliant variety discovered in 1910 in Western Namibia. Heliodor, or Gift from the Sun in Greek, got its name thanks to its vibrant yellow hue. Initially, the name was used to describe only Namibian material, but eventually, all yellow and golden beryl varieties. Heliodor’s vibrant greenish-yellow hue comes from traces of iron. Golden Beryl is a warm yellow or orange-yellow gemstone. However, this distinction is not usually made in the trade, and both terms are interchangeable.
Rare translucent specimens of heliodor with “silk” of tiny needle-like parallel inclusions cut into cabochons exhibit a phenomenon called chatoyancy or cat’s eye.
Pezzottaite is a relatively new beryl specimen with deep pink hues, often confused with red beryl. Pezzottaite has a trigonal crystal structure containing cesium and lithium. It has a variety of trade names, including Raspberyl and Raspberry beryl.
Maxixe Beryl has a deep sapphire-blue color caused by natural irradiation that gradually fades in daylight to a brown-yellow making the stone worthless. It comes from Maxixe Mine in Minas Gerais, Brazil, and a handful of other sources; that’s why the terms ‘Blue Beryl’ or ‘Maxixe-type beryl’ is preferred. It is often irradiated to slow the fading when exposed to light or heat.
Maxixe is not just a type of beryl but also an Afro-Brazilian styling of the two-step polka, brought to Brazil by European immigrants. It is said that the maxixe fad was launched the same year as the Titanic and lasted about as long.
Goshenite, also known as white beryl, is a colorless to near-colorless mineral with hexagonal crystals of exceptional clarity. It is named after Goshen, Massachusetts, a small community near one of the first deposits found in the United States and the home of Three Sisters Sanctuary. The gemstone never caught up in jewelry, but its cute name earned it a small group of fans.