Wednesday, October 02, 2019

Unusual Color-Change Johnkoivulaite Is the Newest Member of the Beryl Family

Johnkoivulaite, a mineral that changes from deep violet to near colorless when viewed with polarized light, is the newest member of the beryl family, which includes emerald, aquamarine and morganite.

The mineral is named after gemologist and author John Koivula, who is best known for his contributions to inclusion research and photomicrography.

The 1.16-carat crystal, shown above, was discovered in the Mogok Valley of Myanmar by local gemologist Nay Myo and confirmed as a new mineral species by the Gemological Institute of America and the International Mineralogical Association.

GIA Senior Research Scientist Aaron Palke unveiled the newly named mineral at the Geological Society of America (GSA) conference on September 25 in Phoenix.

“We are privileged to be able to name this mineral after John Koivula who has contributed so much to science and the gem and jewelry industry as a prominent gemologist and innovator in photomicrography,” said Tom Moses, GIA's executive vice president and chief laboratory and research officer.

The GIA reported that johnkoivulaite has a hardness of 7.5 on the Mohs scale and a hexagonal crystal structure that is very similar to beryl and other members of the beryl group. But, what makes the mineral especially unique is the way it changes from a deep violet to near colorless when subjected to polarized light. This optical phenomenon is called pleochroism.

The johnkoivulaite specimen has found a new home in the GIA museum collection, located at the Institute’s world headquarters in Carlsbad, Calif. Established in 1931, the GIA is recognized as the world’s foremost authority in gemology.

Koivula has more than 40 years of industry experience in research and photomicrography. In 1986, Koivula co-authored with Edward J. Gübelin the immensely popular Photoatlas of Inclusions in Gemstones, followed by two additional volumes. Koivula also wrote The Microworld of Diamonds and co-authored Geologica with Robert Coenraads.

Credits: Photomicrographs by Nathan Renfro/GIA; John Koivula photo by Kevin Schumacher.

Tuesday, October 01, 2019

Neon Blue Paraiba Tourmaline Is the Most Prized Variety of October's Birthstone

Tourmaline comes in a wide variety of fiery, vibrant hues, such as red, green, yellow, orange, brown, pink and purple. October's birthstone is even available in bi-color and tri-color versions. But, the most coveted tourmaline of all is the neon blue variety that was originally unearthed in Paraiba, Brazil, in 1987.

Gemologists learned that Paraiba tourmalines were distinctly different from the rest because they owed their intense blue color to trace impurities of copper. Other tourmalines got their color from the presence of iron, manganese, chromium and vanadium.

Paraiba tourmalines from Brazil are extremely rare, especially in sizes larger than a few carats. That's why the pear-shaped specimen, above, is so remarkable. It weighs 6.69 carats and is the first Paraiba tourmaline to join the National Gem Collection at the Smithsonian in Washington, D.C.

The popularity of Paraiba tourmaline sparked a mining frenzy in Brazil, and within five years, the supply was largely tapped out, according to the Smithsonian. In 2001, new Paraiba-like tourmalines were discovered in Nigeria. Interestingly, the vivid blue-green gems boasted the same color and chemistry as the Brazilian-sourced goods. Then, only one year later, miners in Mozambique reported a similar find.

Today, gem dealers refer to neon blue or green, copper-infused tourmalines as "Paraiba," regardless of their origin. Tourmalines range from 7 to 7.5 on the Moh’s scale of hardness, which makes them durable enough to be used in any type of jewelry. According to, a small, vivid-color Paraiba gemstone will have a greater value than a larger one of lesser color, all other factors being equal.

The name “tourmaline” is derived from the Singhalese words “tura mali,” which mean “stone with mixed colors.”

Tourmaline has been an official birthstone for October since the original list was published by the National Association of Jewelers in 1912. Opal is the month's other official birthstone.

Credit: Photo by Greg Polley/Smithsonian.

Monday, September 30, 2019

Princess Beatrice's New Engagement Bling Is Inspired by Her Grandma's Ring

Princess Beatrice, the granddaughter of Queen Elizabeth II, is rocking a new 3.5-carat diamond engagement ring from Italian real estate tycoon Edoardo Mapellu Mozzi. The ring, which reflects "Victorian and Art Deco fusion," features a round center stone flanked by smaller diamond baguettes in a platinum setting.

Unlike her sister, Eugenie, who got engaged nearly two years ago with an avant-garde padparadscha, Beatrice's bling is said to be inspired by her grandmother's platinum engagement ring, which also has a large white center stone flanked by smaller white diamonds.

The 93-year-old queen has been wearing her ring since the day she accepted Prince Philip's marriage proposal in July of 1947. The prince celebrated his 98th birthday in June.

Eugenie’s ring — an oval padparadscha surrounded by a halo of white diamonds — was strikingly similar in design to the engagement ring of her mother, Sarah, Duchess of York, whose ruby center stone complemented her red hair.

Eugenie’s choice of center stone had sparked the obvious question: What's a padparadscha? Followers of the British royal family soon learned that the beautiful gemstone is one of the rarest and most valuable varieties of sapphire, boasting a rich salmon color.

Beatrice's more traditional engagement ring was revealed in a series of photos posted to Eugenie's official Instagram page. The post included a congratulatory message from Eugenie, along with a comment from the new bride-to-be. The photos were taken by Eugenie on the grounds of Windsor Great Park.

Eugenie wrote, "Beabea - wow! I'm so happy for you my dearest big sissy and dear Edo. It's been a long time coming and you two are meant to be. [Photo] by me!!"

Beatrice added, “We are extremely happy to be able to share the news of our recent engagement. We are both so excited to be embarking on this life adventure together and can’t wait to actually be married. We share so many similar interests and values and we know that this will stand us in great stead for the years ahead, full of love and happiness.”

Beatrice's new fiancé collaborated with British jeweler Shaun Leane on the ring's design. Jewelry experts believe the ring's value is approximately £100,000 ($122,000). The two have known each other for many years, but began dating about a year ago. The couple is expected to walk down the aisle some time in 2020.

Credits: Princess Beatrice images by Princess Eugenie/Instagram. Padparadscha ring screen capture via Royal Family Channel.