May’s birthstone, emerald, is aptly named the gem of spring. Its vibrant green color evokes a lush garden. In fact, inclusions in emeralds are sometimes called an internal “jardin,” the French word for “garden.” The most desirable emeralds range from bluish green to green with vivid color saturation.

If you’re considering an emerald purchase, GIA’s Emerald Buying Guide puts all the information you need at your fingertips, including what quality factors to look for and an explanation why the most common cut of emerald is, appropriately, the emerald cut. Bookmark and share!

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Known for its majestic purple color, amethyst is the gemstone of choice for those born in February. Breathtaking and surprisingly affordable, it’s also the most valued variety of quartz. If you’re in the market for this February birthstone, GIA’s Amethyst Buying Guide has tips and advice on what to look for, including amethyst quality factors.

Share our Amethyst Buying Guide with the February babies you know!

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January’s birthstone, garnet, is known for its impressive variety of eye-catching colors, which can be almost any color of the rainbow. Garnets occur in green (demantoid and tsavorite), orange (spessartine), red (almandine and pyrope), and purplish red (rhodolite), plus a few rare garnets even change color under different types of light. But color is far from a garnet’s only attractive feature.

GIA’s Garnet Buying Guide offers key pointers on what quality factors to look for, and helps you differentiate between some of the garnet varieties, for example two of the green garnets: tsavorite and demantoid.

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September’s birthstone is perhaps most known for the extraordinary sapphire ring worn by Kate Middleton, originally belonging to Princess Diana. Taking a cue from the British royals, celebrities like Penelope Cruz have fueled the colored gemstone engagement ring trend, with sapphire leading the way.

Kashmir sapphire ring from Tiffany’s.

Like its sister gemstone ruby, sapphire is a variety of the mineral corundum. Corundum in its purest form is colorless. These colorless sapphires are popular imitations for diamonds, and have made a comeback as accent stones in recent years. Sometimes when trace elements are present in corundum, color happens. The deep blue hue we most often associate with these gemstonnes results from a combination of the elements titanium and iron. Some combinations of elements can result in colors including purple, green, yellow, orange, pink, and black – the so-called “fancy sapphires.” (A ruby is a ruby and not a sapphire, when the mineral corundum contains enough traces of the element chromium to lend the gem a medium to medium dark red tone.)

Multicolor briolette sapphires interspersed on strands of keshi pearls. Image courtesy of Pearl Exporting Company.

Known as one of the “Big Three” of jewelry gemstones (alongside ruby and emerald), sapphire is a popular and affordable choice. When shopping for a this gemstone, the quality of the cut makes a tremendous difference—a well-cut sapphire will maximize the color.

10.64 carats of round sapphires accented with 7.47 carat of brilliant round diamonds set in 18K white gold. Image courtesy of Omi Prive.

The most common cuts are cushion and oval shapes, as well as emerald, princess and trilliant cuts in stones under a carat. When visiting a jeweler, compare the various shades of sapphire side by side to understand the range of qualities available. Most sapphires you’ll see in jewelry stores are treated by heat or lattice diffusion to alter their color. Lattice diffusion can enhance or change the color, but lattice diffused sapphires are considered less valuable than heat-treated ones. A GIA lab report indicates any detectable treatments and confirms if the sapphire you are considering is natural or synthetic.

Assorted colored sapphires from the Dr. Edward J. Gubelin Collection.

Sapphire is one of the most durable gemstones—it has a hardness rating of 9 on the Mohs scale—which makes it relatively easy to care for. Cleaning this gemstone regularly with just a little mild dish soap, a toothbrush and water is enough to maintain its brilliance.

What is your favorite celebrity sapphire jewelry piece?

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July’s mesmerizing birthstone was called “the king of precious stones” in ancient India. It remains a fitting title today.

Like its sister gemstone sapphire, ruby is a variety of the mineral corundum. Corundum in its purest form is colorless. The trace element of chromium gives corundum a red hue, which can range from orangy red to purplish red. The more chromium found in ruby, the greater the intensity of the red color.

Sapphire and ruby are varieties of the mineral corundum. Image courtesy Hamilton Jewelers.

The history, legend and lore around rubies spans centuries. Warriors in Burma thought rubies made them invincible in battle. Ancient Hindus believed those who offered rubies to the god Krishna would be granted rebirth as emperors. And many medieval Europeans wore rubies to guarantee health, wealth, wisdom and luck in love.

Oval-shaped, 6.16 carat ruby. Image courtesy (c) Christie’s Images/The Bridgeman Art Library.

Ruby is most prized for its color. A pure, vibrant red to slightly purplish-red ruby is considered the most desirable. The purest, most intense ruby color has historically been called “pigeon’s blood”. These rubies have vivid color saturation, which is not too dark. Inclusions in a ruby affect its transparency. Inclusion-free rubies are practically nonexistent, so a ruby’s value partly depends on how visible its inclusions are. Fine-quality rubies over one carat are rare, but are highly prized.

Ruby necklace, earrings and ring.

Treatments are often used to improve ruby’s color, and you can expect the majority of rubies to be heat-treated at the mine. Heating can render a more pure red color, and remove minute needle-like inclusions. Rubies may also be treated with a lead glass-like filling to lessen the visibility of surface-reaching fractures and make the gem more transparent than it really is.

Synthetic rubies are also widely available and at many price points. In fact, in the late 1800s ruby became the first gem to be created in a laboratory. If you’re considering a ruby purchase, expect your jeweler to disclose whether the gem’s been treated or lab-created. And if buying a ruby you might consider purchasing a ruby with a GIA Ruby Report, which will confirm that your stone is, in fact, a natural ruby, identify any known treatments, and even indicate its geographic origin.

Synthetic triangle cut ruby is 3.90 carats and ruby crystal is 162.43 carats.

Ruby is the most durable gemstone, with a hardness rating of 9 on the Mohs scale, so it is relatively easy to care for. Cleaning a ruby regularly with just a little mild soapy water and a soft toothbrush is enough to maintain its fiery luster.

What shade of ruby do you prefer?

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