Fascinating Phenomena in Gemstones

There are several varieties of gemstones that display optical phenomena, which describes the many ways light interacts with the structural features or inclusions (internal characteristics) in the gemstone. Often these gemstones will be fashioned in a particular way that best displays these effects.

The science of optical phenomena can be fascinating, although the mystery and allure of these effects are what initially attract us! Below are six of the most familiar (and magical) displays of optical phenomena in gemstones.

Play-of-Color

Play-of-color is created by a combination of diffraction and interference, and is the result of the microstructure of opal: the chameleon of a thousand colors and October’s birthstone!

Opals are made up of many layers of small, stacked spheres of silica. These spheres diffract light, splitting it into a spectrum of colors. The layers of these spheres create interference allowing certain colors to dominate, depending on the angle the opal is viewed.

Asterism

Asterism, or stars, relates to the four- or six-rayed star pattern of light produced by the fibrous inclusions, elongated needles, or growth tubes in a gemstone. This singular, celestial-like phenomenon is best seen in a gemstone cut en cabochon.

 

Chatoyancy

Chatoyancy [sha-TOY-an-cee] is also known as “cat’s eye.” Fine needle-like or fibrous inclusions within the gemstone are what causes this effect. Again, stones fashioned as cabochons display this effect the best.

 

Color Change

A small number of gemstones display the color change optical phenomena. Depending on the lighting environment, the color change appearance can vary due to the shifting wavelengths. The technical term for this is photochromism or photochroism; “color-change” is a lot easier to say!

The best-known color changing gemstone is alexandrite. When viewed in sunlight, it appears greenish. When placed under incandescent light, it appears reddish. Other varieties of color-changing gemstones include sapphire, garnet, spinel, diaspore, and tourmaline.

 

Adularescence

Adularescence is the phenomenon typically seen in moonstone, which is a member of the feldspar family. It produces a billowy soft blue to milky white light that appears to move across the gemstone. This occurs when light hits the alternating layers of albite and orthoclase, which are two differing forms of feldspar within the gem.

The layers of feldspar interfere with the light rays causing them to scatter and the eye to observe adularescence. The effect is best seen when the gemstone is cut en cabochon [en CAB-ah-shawn]—that is, with a polished, domed top and a flat or slightly rounded base.

 

Labradorescence

Labradorscence [lab-ra-dor-es-cence] is an optical characteristic often seen in labradorite. The effect is a spectacular play-of-color that is metallic or iridescent, displaying blue, green, red, orange, and yellow. This is an interference effect within the gemstone caused by internal structures that selectively reflect only certain colors.

 

Are you ready to see some of these displays in person? Visit an American Gem Society (AGS) jeweler near you and ask to see some gemstones that exhibit optical phenomena!

Go for the Gold!

Throughout history, gold has been one of the most sought-after metals in the world. It’s been used as currency, to decorate objects as a thing of beauty, and is also used for industrial purposes.

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“Reflections” ring made of 24k hammered gold set with diamonds, by Lika Behar Collection.

In the jewelry industry, the word “gold,” when used by itself, means “all gold” or “pure” gold, meaning 24 karat (24K) gold. Because 24K gold is soft, it’s usually mixed with other metals called alloys to increase its hardness and durability. If a piece of jewelry is not 24 karat gold, the karat quality should accompany any claim that the item is gold.

The karat quality marking tells you what proportion of gold is mixed with the other metals. Fourteen-karat (14K) jewelry contains 14/24 or 58.3% gold, with 10/24 parts of an alloy metal. The higher the karat rating, the higher the proportion of gold in the piece of jewelry.

Jewelry should be marked with its karat quality. Near the karat quality mark, you should also see the name or the U.S. registered trademark of the company that will stand behind the mark. The trademark may be in the form of a name, symbol or initials. If you don’t see a trademark accompanying a quality mark on a piece of jewelry, look for another piece.

Are you ready to go for the gold? Below are some designs from our American Gem Society members that feature yellow, white, or rose gold, which is a mixture of gold with copper to create the pinkish, soft glow.

 

 

When it comes to cleaning gold, visit your jeweler for a professional cleaning. To clean your jewelry at home, be sure to ask your jeweler what at-home products are best for cleaning gold, especially if there are gemstones in the piece.

Four Fine Jewelry Trends for Spring 2019

Spring is here and we’re ready for some jewelry trends to help us celebrate this much-welcome change of season! Now that the weather is warming up, what’s hot? We’ve gathered some season-sensational (We just made that up!) designs from our AGS members.

Quite possibly the most quintessential symbols of spring are flowers, butterflies, and bees. Naturally, their likenesses are found in a variety of fine jewelry designs.

 

Next on the list is chains. Big chains. Little chains. This trend is an ode to the Eighties and they’re everywhere!

 

It’s been said that pearls never go out of style, but these aren’t your grandmother’s pearls! Modern designs have re-imagined the classic jewelry wardrobe staple.

 

The warmer weather has us looking towards the sky and the sea for a much-needed getaway! Both celestial and nautical-themed designs inspire us to seek the outdoors (and beyond) for our next adventure.

 

Are you ready to add a bit of bling to your spring wardrobe? Find an American Gem Society jeweler member near you at www.ags.org/findajeweler.

3 Gemstones That Sparkle for the 4th of July

By Robin Skibicki

Dilamani

Ruby, diamond, and sapphire brooch by Dilamani.

The American Independence Day—or the Fourth of July—is when we celebrate our country’s freedom and the adoption of the Declaration of Independence. It’s also considered the height of summer!

It’s a time for family reunions, barbeques, picnics, parades, and the much-anticipated fireworks displays. On this day, we proudly display our nation’s colors: red, white, and blue.

Fun Fact: More than 14,000 firework displays are put on across the country on the Fourth of July!

But don’t let those fireworks grab all the attention. Create your own sparkle-fest with three gemstones that will beautify your patriotic style. We’re talking about rubies, white diamonds, and blue sapphires!

In honor of the holiday, we’ve picked a few designs by our American Gem Society members that feature one of the three, aforementioned gemstones. Click on each image below to get a closer look.

Red Rubies

 

White Diamonds

 

Blue Sapphires

 

May your Fourth of July celebration be sensational, safe, and full of sparkle! To find an AGS-credentialed jeweler near you, visit http://www.ags.org/findajeweler.

Celebrate the Woman Who Means Everything

By Robin Skibicki

“Being a mother is about learning about strengths you didn’t know you had and dealing with fears you didn’t know existed.” – Linda Wooten, author.

When I was 9 years old, I asked my Mom on Mother’s Day why there isn’t a Children’s Day. Without hesitation, she responded in a kind but firm voice, “Honey, EVERY DAY is Children’s Day.” I knew that tone and I also detected that wasn’t the best question to ask at that moment.

Now that I’m a mom, I get it! In fact, I believe mothers truly need more than one day a year to call their own. How about once a month? The list of gratitude towards our mothers can be infinite, from the little things, like kissing a “boo-boo,” to jumping in with all her heart and soul to help us through a rough situation.

Nowadays, we realize that Mother’s Day isn’t just about mothers. The holiday extends to celebrate all the incredible women who have made significant contributions in our lives, helping us become who we are today. She can be a stepmom, mother-in-law, grandmother, daughter, daughter-in-law, aunt, sister, cousin, friend, teacher, or mentor.

If you are looking for a gift that is beyond special and significant for a fabulous female in your life, consider fine jewelry. They’re not only gifts that will make her smile (possibly with a glistening tear in her eye) once she opens it, but each day she wears it. She will treasure it for years to come and it will ultimately become a cherished heirloom.

The credentialed members of the American Gem Society (AGS) have got you covered for Mother’s Day. Here are a few ideas to get you started. If there is a design you like or have an idea of your own, contact an AGS jeweler near you!

Bring on Spring: Be Inspired by the Colors of the Season

“April hath put a spirit of youth in everything.” – William Shakespeare

Now that spring has arrived, we look forward to the signs of renewal. From fastidiously cleaning our homes and joyously changing out our wardrobe to reconnecting with family and friends for a spring holiday or wedding. It’s easy to love this time of year!

Even our jewelry is complementing the seasonal spectrums, with soft pastels and bright, happy colors. Here are some spring-inspired styles from a few of our American Gem Society (AGS) members.

 

We’ve all got that extra spring in our step thanks to the warmer weather and the chance to don the colors of the season in our homes, wardrobe, and fine jewelry! Search for an AGS-credentialed jeweler near you and they’ll help you find the perfect piece for any springtime occasion.

Six Displays of Optical Phenomena in Gemstones

By Robin Skibicki

There are several varieties of gemstones that display optical phenomena, which describes the many ways light interacts with the structural features or inclusions (internal characteristics) in the gemstone. Often these gemstones will be fashioned in a particular way that best displays these effects.

The science of optical phenomena can be fascinating, although the mystery and allure of these effects are what initially attract us! In this article, we’ll discuss six of the most familiar (and magical) displays of optical phenomena in gemstones.

Adularescence

Adularescence is the phenomena typically seen in moonstone, which is a member of the feldspar family. It produces a billowy soft blue to milky white light that appears to move across the gemstone. This occurs when light hits the alternating layers of albite and orthoclase, which are two differing forms of feldspar within the gem.

The layers of feldspar interfere with the light rays causing them to scatter and the eye to observe adularescence. The effect is best seen when the gemstone is cut en cabochon [en CAB-ah-shawn]—that is, with a polished, domed top and a flat or slightly rounded base.

 

Asterism

Asterism, or stars, relates to the four- or six-rayed star pattern of light produced by the fibrous inclusions, elongated needles, or growth tubes in a gemstone. This singular, celestial-like phenomenon is best seen in a gemstone cut en cabochon.

 

Chatoyancy

Chatoyancy [sha-TOY-an-cee] is also known as “cat’s eye.” Fine needle-like or fibrous inclusions within the gemstone are what causes this effect. Again, stones fashioned as cabochons display this effect the best.

 

Color Change

A small number of gemstones display the color change optical phenomena. Depending on the lighting environment, the color change appearance can vary due to the shifting wavelengths. The technical term for this is photochromism or photochroism; “color-change” is a lot easier to say!

The best-known color changing gemstone is alexandrite. When viewed in sunlight, it appears greenish. When placed under incandescent light, it appears reddish. Other varieties of color-changing gemstones include sapphire, garnet, spinel, diaspore, and tourmaline.

 

Labradorescence

Labradorscence [lab-ra-dor-es-cence] is an optical characteristic often seen in labradorite. The effect is a spectacular play-of-color that is metallic or iridescent, displaying blue, green, red, orange, and yellow. This is an interference effect within the gemstone caused by internal structures that selectively reflect only certain colors.

 

Play-of-Color

Play-of-color is created by a combination of diffraction and interference and is the result of the microstructure of opal: the chameleon of a thousand colors!

Opals are made up of many layers of small, stacked spheres of silica. These spheres diffract light, splitting it into a spectrum of colors. The layers of these spheres create interference allowing certain colors to dominate, depending on the angle the opal is viewed.

 

Are you ready to see some of these displays in person? Visit a credentialed AGS jeweler near you and ask to see some gemstones that exhibit optical phenomena!