October Birthstone: Opal

opal-ring

While the colorful glory of the opal is undeniably striking. Opals range in color from white to black, with glints of yellow, orange, green, red and blue. They derive their name from the Greek word Opallos, which means “to see a change (of color).” Opals were formed by non-crystalline silica gel that seeped into crevices within sedimentary strata. Over time the gel hardened to form opals. They’re essentially composed of particles closely packed together in delicate arrangements. When these particles are packed together in a regular pattern, they create a three-dimensional array of spaces – which create the opal’s unique radiance.

For more info: http://www.gia.edu/opal

 

Advertisements

September birthstone: Sapphire

Sapphire is a popular gemstone – and comes in a rainbow of colors. It’s also been long prized, from Ancient Greek rulers to the clergy of the Middle Ages. But where does the September birthstone come from?

A Little Bit about Sapphire

Sapphires in a range of colors

Before we embark on our journey to find the September birthstone, let’s start with a little gemological background.

The September birthstone, sapphire, comes in a range of colors: blue, violet, green, yellow, orange, pink, purple and intermediate hues. The gem belongs to the mineral species corundum: corundum is colorless, but trace elements or color centers (small defects in the atomic structure of a mineral that can absorb light and impart color to the stone) can turn colorless corundum into colorful sapphire. Red corundum is the only color not called sapphire; corundum with this color is ruby.

Where Sapphires Come From: Kashmir

3.08 ct unheated Kashmir sapphire

Blue Kashmir sapphire is legendary among gem collectors and jewelry connoisseurs. However, its reputation for gems of unsurpassed beauty rests on stones mined from 1881 to 1887; very little has been produced since then. Sapphire from the mines after this brief window in time varied greatly in quality.

Finding the September birthstone in Kashmir reads like a chapter from an adventure book: we go to northern India, past the picturesque Dal Lake and its famous houseboats, beyond fields of wildflowers and head up into the Himalayas. Our journey takes us on treacherous roads to, as 18th-century explorers described, a “region beyond the snows.” In these remote hillsides, some of the world’s most beautiful sapphires were unearthed.

Srinagar

Fine blue Kashmir sapphire is said to resemble the color of the feathers of a peacock’s neck. Tiny inclusions give gems a velvety appearance. This can look like an extremely fine haze.

A few last facts about Kashmir sapphire: perpetual snow cover makes mining extraordinarily difficult; the mines are exceedingly remote; the weather is severe; and the area is politically contested. Few stones sporadically emerge, and fewer gemologists have researched the mines. That means you’re highly unlikely to find Kashmir sapphire for sale, and if you do, you’ll want a GIA Colored Stone Identification & Origin Report to verify its country of origin. Fine pieces are occasionally sold by leading auction houses.

Blue sapphire

Where Sapphires Come From: Myanmar

rough sapphire crystal

The land north of Mogok, a city in Upper Myanmar. Blue sapphires mined in Mogok tend to have a rich, intense hue; the best of these September birthstones maintain their appearance under all lighting conditions: incandescent, daylight and fluorescent.

Miners outside of Sapphire mine in Mogok

The sapphire mines of Mogok share some similarities with the ones from Kashmir: they are remote, hard to reach and are in a politically-charged land. Sapphires from this locale are also rare; they are found near many of the ruby deposits. Mogok is also famed for producing some of the finest pink sapphires in the world.

oval shape 6.39 ct pink sapphire

Where Sapphires Come From: Sri Lanka

Sri Lanka can poetically be called “Treasure Island”. All colors of sapphire, ruby, cat’s-eye chrysoberyl, spinel, garnet, tourmaline, topaz, quartz and many other gems can be found in the Highland Complex, a wide band that runs roughly down the middle of the island. Some of the finest sapphire is also found here, and in riverbeds scattered across the country.

Miner searching in river gravel

33.16 ct blue sapphire

6.66 ct padparadscha sapphire

Sri Lanka is perhaps the most famous source for padparadscha sapphires; they are found in river gravel throughout the country. Padparadscha means “lotus flower,” in Sinhalese and this name has been given to the pinkish orange to orange-pink variety of corundum. This sapphire’s color has been likened to the color of salmon, sunset and ripe guava. The cause of color for padparadscha sapphire is due to either trace amounts of iron and chromium or color centers. Fine specimens can sell for as much as a ruby.

Sri Lanka is also a source of the September birthstone in many of its colors: green, yellow, pink, purple, and virtually any color in between. Many in the trade consider Sri Lanka to produce the best range of fancy color sapphires in the world.

Where Sapphires Come From: Thailand

Thailand is an important source of sapphire. Gem fields in Chantaburi, in southeastern Thailand, were mined from the late 1800s to the early 1900s. Sapphire now mostly comes from Kanchanaburi (western Thailand), where it is found in rivers and streams. Most sapphire mined in Thailand is heat-treated to improve its color.

Sapphire mines in Kanchanaburi

Thailand is one of the world’s major cutting and treatment centers: sapphire from Myanmar, Cambodia, Australia, Madagascar and Sri Lanka are sent here, and end up in jewelry stores in the United States, Japan and Europe.

Art Deco bracelet

Where Sapphires Come From: Cambodia

On the western side of Cambodia—in the Pailin Province, near the border with Thailand—sapphire rough lies in riverbeds. Miners sift through the gravel, looking for “Pailin sapphire,” which is understood to be fine-quality blue sapphire that is typically water-worn, rounded and hexagonal in shape. Stones are regularly heat-treated to lighten color and remove or reduce inclusions.

Pailin, Cambodia

Mining for sapphire in Pailin is extremely demanding. Deadly malaria and a hot climate are working conditions that require muscle and grit. The Khmer Rouge, an oppressive regime that ruled Cambodia from the 1970s to the 1990s, left a legacy of poverty and landmines that still take lives and limbs. Still, in the midst of these most difficult circumstances, miners search for a piece of rough that can change their fortunes.

Two 11.48 carats blue sapphires

Where Sapphires Come From: Madagascar

Three blue sapphires

Madagascar, an island off the southeastern coast of Africa, is a rich source of gems: garnet, aquamarine, tsavorite, rubies and of course, the September birthstone. Rough sapphire was found in 1993 in the Andranondambo region of southern Madagascar; and in 1998 in IIakaka – a remote, arid land of plains broken by lonely mountains. A new source was found in January 2016 near Andranondambo in an extremely remote and dangerous location. The mine is accessible only by foot, and the area is rife with bandits.

Sapphire mining in Madagascar

Many people rank the color of Madagascar’s blue sapphires between Kashmir and Sri Lanka in quality. Rough is often heat-treated to improve color. Slight inclusions are common, as well as color zoning (bands of color).

Two heat-treated Madagascar sapphires

Madagascar is another source for fancy color sapphire: it produces pinks, blue-violets, yellows, oranges and greens.

Range of different colored sapphires

Where Sapphires Come From: Other Sources

The September birthstone can also be found in other areas of the world. Australia produces blue, yellow and green sapphires. It is primarily a source of commercial-grade sapphire, and occasionally produces high-quality rough suitable for use in fine jewelry. Commercial-grade sapphire is also found in Montana. Tanzania, Malawi and Kenya – countries in East Africa – are other sources of pink, blue-violet, yellow, orange and green sapphires.

Heat treated yellow sapphire (left) and untreated yellow sapphire (right)

18K yellow and rose gold flower pin

 

Courtesy of GIA

 

August birthstone: Peridot

Placeholder Alt Text
While the 64.57-carat cut peridot is magnificent, it is overshadowed by the amazing 7.9-cm tall crystal. Both are from Sappat, Kohistan, Pakistan- Jeffrey Scovil.

Gem miners find peridot as irregular nodules (rounded rocks with peridot crystals inside) in some lava flows in the United States, China, and Vietnam and, very rarely, as large crystals lining veins or pockets in certain types of solidified molten rock. Sources for the latter include Finland, Pakistan, Myanmar, and the island of Zabargad.

Suite of Peridot Jewelry

This incredible suite of peridot jewelry has a total weight of 350.40 carats. All are top-quality peridots from Pakistan. – © GIA & Harold & Erica Van Pelt.

Geologists believe both types of deposits relate to the spreading of the sea floor that occurs when the earth’s crust splits, and rocks from its mantle are pushed up to the surface. Sometimes—as in Myanmar— these rocks can be altered, deformed, and incorporated into mountain ranges by later earth movements.

Rarely, peridot can have an extraterrestrial source, being contained in meteorites that have fallen to earth.

The color range for peridot is narrow, from a brown-green color to yellowish green to pure green. Yellowish green is the most common peridot color seen in jewelry.

Princess Cut Peridot

Peridot is best known for its yellowish green color.

Peridot is the gem variety of the mineral olivine. Its chemical composition includes iron and magnesium, and iron is the cause of its attractive yellowish green colors. The gem often occurs in volcanic rocks called basalts, which are rich in these two elements.

Healing Sisters

These peridots from Peridot Mesa in the San Carlos Apache Nation, Arizona, are set in a jewelry style called “Healing Sisters.” – Courtesy Apache Gems

Placeholder Alt Text
Courtesy of GIA

July birthstone: Ruby

round ruby ring

Since ruby has been used as a gemstone for centuries, it can be seen in a variety of styles, from Indian jewellery to Art Deco and contemporary fine jewellery. Ruby is a durable material that can be worn daily as rings, earrings, necklaces and so on. In Indian style jewellery, rubies are often mixed with emeralds and diamonds. Gold settings provide a striking contrast to the red of ruby. Modern jewellery settings for ruby include white gold and platinum, whereas traditional settings tend to be gold. Small rubies can be set closely together in an intricate style such as bead setting or “pavé”, which was made famous by jewellery designers such as Joel A. Rosenthal, known simply as JAR, who created exquisite flower jewels from colored gemstones.

Note: Buy colored gemstones by size and not by carat weight. Colored stones vary in size-to-weight ratio. Some stones are larger and others are smaller than diamonds by weight in comparison.

Ruby Gemstone Jewelery Care and Cleaning

Rubies are tough and durable, so they do not require any special care. To clean your rubies, simply use warm soapy water and a soft cloth. Fracture-filled and diffusion-treated gemstones should only be cleaned with a damp cloth. As with most gemstones, ultrasonic cleaners and steamers are not recommended. Always remove any jewellery or gemstones before exercising, cleaning or engaging in harsh physical activities such as sport. Do not expose rubies to acid and store rubies away from other gemstones to avoid scratches. It is best to wrap gemstones in soft cloth or place them inside a fabric-lined jewellery box.

ruby set

For more info on Ruby, click on link below:

ruby rough

http://www.gia.edu/ruby

 

 

 

 

 

May Birthstone: Emerald

 

Emerald is the green to greenish blue variety of beryl, a mineral species that also includes aquamarine as well as beryls in other colors.

emerald neck

Gem experts differ on the degree of green that makes one stone an emerald and another stone a less-expensive green beryl. Some people in the trade tend to give the name emerald to any green beryl colored by chromium. But to most gemologists, gemological laboratories, and colored stone dealers, it is more correct to call a stone green beryl when its color is “too light” for it to be classified as emerald. Even among that group, however, there’s a difference of opinion about what’s considered “too light.”

rough emeralds

GIA uses lab-graded comparison stones to determine if the green color is dark enough and saturated enough to be called emerald.

round emerald ring

For more info on Emerald, visit  https://www.gia.edu/emerald#

 

 

April Birthstone: Diamond

diamond shapes

A diamond is a stone that truly states, “I love you” in a deep way. In fact, you’ve probably heard the slogan many times that “a diamond is forever.” This is because of the stone’s symbol of deep, everlasting love, as well as the fact that it’s the hardest substance known on earth.The diamond is also the stone that marks the 60th anniversary of marriage, and is the birthstone for the month of April. It is believed that the first diamonds were discovered in India. In Ancient India, people viewed diamonds as religious icons.
Australia-origin-of-diamond.jpg Going back to early history, diamonds were always used to engrave tools because of their hardness. Diamonds have been found all over the world on all continents. In 600 AD, diamonds were found in Borneo, an island located north of Australia. In the 1700’s, Brazil was a rich source of diamonds, and in the 1800’s, South Africa was known for their large supply of diamonds. Since the 1970’s, Australia has been a large source for the precious stones.
Greek-warrior-history-of-diamond.jpg

Ancient Greeks named the diamond “adamas,” meaning “invincible,” “indestructible,” “proper,” and “untamed.” Warriors in ancient Greece wore diamonds as the stones were thought to strengthen the warriors’ muscles and bring them invincibility. The power, hardness and beauty of the diamond have been prized throughout history in many civilizations. The famous Persian poet Hafiz remarked that, “the rainbow is confined in a diamond forever”. In antiquity, a diamond was always thought to be a symbol of innocence and purity. Ancient Greeks thought that diamonds represented the tears of weeping gods. Ancient Romans thought diamonds were considered to be parts of the outer rings of stars, which had fallen to the earth.

diamond-history-napolean-strength.jpg Almost every civilization has some kind of lore on the diamond. Every civilization’s lore however, shares one theme- that the diamond symbolizes all forces necessary for a healthy society, and that it brings its wearer great strength. The diamond was always considered a stone of winners. In fact, it was the talisman of Julius Caesar, Louis IV and Napoleon.
rennaisance-period-diamond-history.jpg

The Renaissance Period was the first point in time when diamonds were used as engagement rings. They were thought to be a special gift, which represented the very ultimate gift of love. In 1477, this trend was started when Archduke Maximillian gave Mary of Burgundy a diamond engagement ring. This was a trend that was only popular among royalty and the very wealthy.

diamonds-facts-jewelry-rings.jpg Giving a diamond as an engagement ring did not actually become a standard until the De Beers marketing campaign started, during the 20th Century. Today, the primary use of diamonds is no longer for carving or protection during battles. They are now used for adornment because of the their sheer beauty- their dispersion of white light into many different beautiful colors, and their brilliance and indestructibility. Gemologists now rate diamonds based upon what is called “the 4 C’s,” referring to carat, cut, color, and clarity.
the-4-c-of-diamonds.jpg

“Carat” refers to the weight of the diamond. “Cut” refers to the brilliance of the stone, as the way it is cut determines how much brilliance a diamond will have. “Clarity” refers to the natural blemishes found inside diamonds (and remember, a flawless diamond is extremely rare). Finally, “color” is the last important factor when choosing a diamond. The highest color ranking for a diamond represents a completely clear and colorless stone.

Physical Properties and Science of Diamond

carbon-atom-facts-about-diamonds.jpg

As the hardest mineral in existence, a diamond is highly regarded for its beauty and ability to reflect light in an extremely dazzling way. Diamonds display a large amount of brilliance and fire, meaning they sparkle a lot, and always retain a freshly polished look.Created out of pure carbon, the carbon atoms within diamonds are bonded very strongly, which makes for the hardness and strength of the stone. Diamonds are the hardest known substances.

durability-diamond-jewelry-birthstone.jpg Because of the strength of this carbon bonding, diamonds rate a 10 on the Mohs scale- meaning they are as hard as a stone could possibly be. Since antiquity, it has been known that diamonds are the hardest stone. Because of this, the hardest diamonds can only be scratched with other diamonds. Also because of their hardness, not too much care is needed to keep your diamond looking new. It keeps a polish for a very long time and is therefore suitable for everyday wear. Other chemicals cannot affect diamonds, because they are the most durable and inert material.
colored-diamonds-gemstone-jewelry.jpg

In their most natural form, diamonds are clear, but because of impurities of light elements, such as nitrogen, diamonds can also be found in colors such as orange, green, blue, pink, black, yellow, orange, green, red, and brown.

diamond-light-refraction-facts.jpg The brilliance of a diamonds comes from a combination of reflection, dispersion, and refraction. A ray of light first passes through a diamond and is then bent, or refracted. Then, this bent ray is reflected through a facet at the bottom of the stone and through the top of the stone. When refraction occurs, each ray is bent at a slightly different angle, which is referred to as dispersion. Of all gems, diamonds have the highest index of refraction.
brilliant-cut-diamond-jewelry.jpg

The most popular cut of diamond is called a brilliant cut, a cut where numerous facets are placed so the most rays of light will reflect through them. This cut is determined by mathematical and empirical analysis. A Brilliant cut does not refer to the shape of the actual stone, but the proportion and symmetry of the diamond.

 

For more info on diamonds, click on: https://www.gia.edu/diamond

%d bloggers like this: