GIA

GIA

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May's birthstone, emerald, is the ultimate green gemstone. ❇️ Ancient and beloved for millennia, these precious gems belong to the beryl family and formed as long as 2.97 billion years ago. They are colored by chromium and vanadium. The first known emerald mines were in Egypt, dating back to at least 330 BCE. In the 1500s, the Spanish conquistadors brought South American emeralds from Colombia all over the world. Today, the biggest producers are Colombia, Zambia and Brazil. Fun fact: Emeralds are the only gemstone to have a cut—the emerald cut—named after them! Learn more about May’s birthstone on our website.

05.01 22:02

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Looking for blue-tiful gemstones that are also incredibly durable? Save this list! 💙🩵 Durability is an important factor for frequently worn jewelry such as engagement rings. If you’re looking for your “something blue,” make sure you save this list! - Blue diamond tops the list with a Mohs scale rank of 10! Ultra-rare, brilliant and with a formation story linked to the sea, it is also the hardest blue gemstone. Its smoky blue color gives it a mysterious aura, as does its occasional red fluorescence. - Sapphire is next as a true-blue classic. Its most popular colors are a rich royal or cornflower blue. - Cobalt spinel is an ultra-rare stunner. If you can get your hands on one, its vivid, neon blue color is hard to beat. - Blue topaz is known for its vivid azure “Swiss blue.” It is the most widely available and affordable blue gemstone. - Aquamarine, with its soothing greenish blue to blue hues, is associated with sirens and mermaids and said to protect sailors! - Paraíba tourmaline can come in neon blue hues that are highly desired. A 7-7.5 on the Mohs scale, they can require a bit more care than other gems on this list. See the full list of must-know gemstones on our website at the link in our bio.
Cushion cut diamonds are elegant classics with both vintage and modern appeal. Save these tips for the next time you’re looking for one: - Modern or Vintage: Cushion cuts come in styles like old mine, cushion brilliant, and modified cushion. The old mine cut dates to the 1700s and features a squarish shape, high crown, deep pavilion, small table and large culet—distinct from modern cuts. Cushion brilliant cuts have square to rectangular outlines with curved sides and rounded or pointed corners. Modified cushion cuts include extra facets for different light return effects. - Facet Arrangement and Symmetry: Balanced curves and corners improve visual appeal. Cushion cuts vary in length-to-width ratio from square to elongated. Because of the range in facet arrangements, cushion cuts can sparkle very differently—viewing in person is best to assess brilliance and pattern. - Girdle: Cushion cut girdles are often thicker at the corners and should be durable enough for setting. Learn more about cushion cut diamonds on our blog at the link in our bio.
GIA's services for laboratory-grown diamonds are getting an important update 💎 In Q3, GIA will adopt new descriptive terms for characterizing laboratory-grown diamonds, replacing the traditional 4Cs nomenclature that was designed for natural diamonds. “Similar to other man-made gem materials, we anticipate the continued acceptance and popularity of laboratory-grown diamonds,” said Tom Moses, GIA executive vice president and chief laboratory and research officer. “More than 95% of laboratory-grown diamonds entering the market fall into a very narrow range of color and clarity. Because of that, it is no longer relevant for GIA to describe man-made diamonds using the nomenclature created for the continuum of color and clarity of natural diamonds.” Read the full press release at the link in our bio.
Luminous, color-changing or dreamy? 🧐 June babies are lucky to have not one, not two, but three phenomenal birthstones: pearl, alexandrite and moonstone! These gems are “phenomenal” not just for their beauty, but because they display unique optical effects, known as “gemstone phenomena,” created by light interacting with their internal structures. - Pearl is cherished for its soft, luminous glow. Its nacre scatters and interferes with light to create a gentle radiance, and sometimes a rainbow-like shimmer, called orient, that floats across the surface. ⚪️ - Alexandrite is a rare, color-changing gem known as “emerald by day, ruby by night.” The finest specimens shift from green in daylight to red under incandescent light. 💡 - Moonstone is named for its dreamy, glowing sheen. This mystical effect, called adularescence, comes from light scattering across layers of feldspar within the gem. 🌙 Which of these truly phenomenal birthstones would you choose? Learn more about June birthstones at the link in our bio.
Blue diamonds are already some of the most fascinating gemstones in the world, but did you know they can also conduct electricity? They can if they are natural color type IIb. ⚡️💎 Here’s why: Boron is the magical ingredient that causes diamonds to turn blue and conduct electricity. Pure diamond consists of covalently bonded carbon atoms, where each atom’s 6 electrons are tightly bound, making it an excellent electrical insulator. However, substitutional boron atoms only have 5 electrons, creating electronic “holes” in the diamond crystal lattice, creating a pathway for electrical conduction. Boron atoms can be compensated by nitrogen atoms in the crystal, “accepting” electrons that are “donated” by the latter atoms. The higher the concentration of uncompensated boron – and the deeper the blue color – the higher the electrical conductivity! Laboratory-grown diamonds that contain boron are also electrically conductive. However, blue diamonds that are colored by vacancies formed by natural or artificial irradiation do not conduct electricity! Learn more about blue diamonds and their fascinating properties in a recent issue of G&G at the link in our bio.
May’s mystical birthstone has been a favorite for thousands of years. Save our easy guide to know how to pick the best emerald: COLOR: Pure green and bluish green gems are more desirable than yellowish green ones. CLARITY: An emerald’s inclusion scene is sometimes called its “jardin” or garden in French. Many emeralds contain fissures that require oiling (see Treatment below). CUT STYLE: The emerald cut is the most popular cut style, but oval and round shapes are popular as well. CARAT WEIGHT: Emeralds are less dense than diamonds and appear larger for the same carat weight. TREATMENT: Many emeralds have fissures that are filled with oils or natural resins. GIA identifies filler type and classifies this clarity enhancement as Minor, Moderate or Significant. Gems with Significant enhancement may have durability issues. Also watch out for dyed gems imitating emerald. CARE: Emeralds should never be placed in ultrasonic or steam cleaners, which may damage their filler. Instead, clean them with warm, soapy water and a toothbrush. Learn how to pick the best emerald for you at the link in our bio.
Women have power-dressed with emeralds for centuries—from Cleopatra and Catherine the Great to Sofia Vergara, Michelle Yeoh and Zoe Kravitz. Emeralds, with their rich, magnetic glow, represent power, rebirth and mystique. ❇️ What better jewel to evoke power with than the Rosenkrantz emerald necklace? Seen here, it features a 162.50-carat Colombian emerald surrounded by step cut diamonds and emeralds. This necklace was designed by Jhaleh Aziz Rosenkrantz, co-owner and creative director of Rosenkrantz Africa, a designer with Tanzanian and Iranian roots who sources gems from artisanal miners all over the world. What do you think of this stunning piece? Photo courtesy of Jhaleh Aziz Rosenkrantz
Save this list of must-know yellow gemstones! 🌟 Throughout history, yellow gems have evoked sunshine and represented joy, warmth and optimism. ☀️ - The most valuable and durable yellow gem is fancy-color yellow diamonds, with the most famous being The Tiffany Diamond. - Yellow sapphire stuns with its radiant sunny color. - Citrine is affordable and available in very large sizes. - Topaz is known for its golden glow. - Heliodor beryl offers a range of lime, lemon and golden hues. - The most fiery (but also the softest) yellow gemstone is sphene with its out-of-this-world brilliance and fire. What’s your favorite yellow gemstone? See the full list of must-know gems on our website at the link in our bio.
This 7-carat Fancy Intense purplish pink diamond was the headliner of Sotheby’s December 2024 Magnificent Jewels auction, where it sold for USD $3.4 million. That’s roughly $486,000 per carat! 💗 Pink and purple diamonds are some of the rarest, most desirable gems in the world. This unique diamond is a mix of both. GIA researchers believe that pink and purple coloring occurs when diamond crystals are exposed to high pressures deep in the Earth, causing the crystal to deform, modifying the arrangement of the atoms. Pink graining is evidence of this plastic deformation, selectively absorbing light. Sometimes, these “imperfections” in the crystal create absolute perfection! Learn more about colored diamonds on our website at the link in our bio. Stone image courtesy of Sotheby’s Image 2 courtesy of Sotheby's
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