While most likely known by a large population of jewelry collectors, not everyone is familiar with the fact that sapphires can actually come in a wide variety of colors. Let's start first with a little bit of basic chemistry- Aluminium oxide (Al2O3) that naturally crystallises in the trigonal atomic lattice system forms as a gem species properly called corundum. Now, corundum is not a word you would often hear while talking shop with socialites at parties, but within this gem species rests two of the most famous gem varieties in the world of colored gemstones- ruby and sapphire.



Ruby is actually red corundum, drawing its color from the presence of a trace element called Chromium. A few parts-per-million is enough to interact with the gemstone's chemistry to produce the red color widely coveted in the fine jewelry trade. Meanwhile, trace elements like iron and titanium can be responsible for producing a violetish-blue color, which results in the corundum specimen being designated to the blue sapphire variety.

Ruby and sapphire have very similar chemistry, with minuscule differences in the trace elements that create their differences in color. Sapphire though, is not always blue. While its bluish variety is indeed the most popular, sapphires can also come yellow, pink, green, purple, black, colorless and many other hues of the rainbow. Some of these hues may commonly occur in higher saturations than others. For example, violet-purple and green colored sapphires can appear grayish or muted in intensity, at least when compared to other gemstones of similar color (such as amethyst or emerald). All color of sapphire other than blue are grouped up and called 'fancy colored sapphires'.



The global gem market for sapphires is very diverse today. The biggest or most popular demand surges usually target blue sapphires, Padparadscha sapphires (pinkish-orange) and pink sapphires. Vivid yellowish sapphires are also commonly used, especially in seasonal tandem with the trendy color palettes governed by the fashion industry. Colorless sapphires (especially the lab-grown or synthetic versions) are sometimes utilised as diamond imitations as well, although their dispersion and brilliance are noticeably different from those of diamond.

Many sapphire colors are also produced by heating, or other more complicated enhancement procedures- like diffusing beryllium as a coloring agent into the stone's crystal lattice.

Also do keep in mind that synthetic corundum (lab-grown ruby and lab-grown sapphire) is a very common sight in today's jewelry marketplace. The flame-fusion process of creating man-made sapphire / synthetic sapphire is very widespread across many international manufacturers. Synthetic product can be created and sold at very low prices, as the creation technology (pioneered in the late 1800's) has grown accessible and affordable for many mid-scale entrepreneurs to get into.



Other similar creation methods, like the Czochralski process of growing crystal, are also being used today- not solely just for the jewelry industry, but also for military and industrial purposes as well. This is mainly due to corundum's high hardness (9) and general durability, as well as some of its other properties.

Many connoisseurs in the jewellery trade are familiar with the annual auction events held internationally. From Geneva to New York, greatly anticipated events led by the duopoly of Christie's and Sotheby's auction houses, have shown us some of the world's most tantalising jewellery from human history's most well known brands and designers.




Photography: Sotheby's Auction House, Plume necklace by Jean Schlumberger (Tiffany & Co.)

One particular storyteller we often like watching (just for his charismatic narration of significant pieces) is Frank Everett, who spotlights his own section called Frank's Files, on Sotheby's online platform. Here's an episode link where he timelessly describes a couple of novelty pieces from the collections of Barbara Sinatra (wife of Frank Sinatra) and Happy Rockefeller.



Some of the oldest jewellery design houses in the western world are often featured on his segments, including pieces by Cartier, Van Cleef & Arpels and Tiffany & Co. Both diamonds and rare coloured stones are often incorporated within the same piece, creating a mysterious allure unbound by a single hue or theme. Rubies, emeralds and sapphires are among the world's highest priced gemstones, and they're often found in the collections of society's most well regarded socialites and personalities.

The “Big Three” as they’re often called, constitute the vast majority of colored gemstone sales across most international markets. Rubies are traditionally the most expensive among them, given similar quality levels, however in the U.S. sapphire is more frequently purchased by end-consumers.

Depending on your familiarity with gemstones and gemology, you might find it surprising to know that rubies and sapphires are very similar to each other on an atomic level. Both are composed of crystalline aluminum oxide, but are colored by different trace elements. Chromium is responsible for ruby’s vibrant reds, while iron and titanium cause the violetish blue hues of sapphire.



Identification of a gemstone species involves taking note of different gemological traits. When checking rubies for example, our gemologists here at Gemcamp factor in tests that determine properties like optic character, growth structures, birefringence, refractive index and many others. Each gemstone species has its own unique and definable values that allow gemologists to separate it from another similar looking species. Red spinel for example can look identically similar to ruby by just the naked eye, however its crystal structure is actually more symmetrical on an atomic level compared to ruby’s. This can be observed using a polariscope, giving our gemologists information that they can use to scientifically pinpoint a gemstone’s proper identity.

Emeralds are composed of different elements altogether, they are beryllium cyclosilicates. Here at the laboratory, we also look for clues and indicators of identity under the microscope. Mineral inclusions such as pyrite can help us separate natural emerald from man-made emerald- which can be created today using a variety of proprietary methods. Chatham and Tairus are two companies abroad who have pioneered the development of artificial gem growth. They regularly produce man-made emeralds among many other gem species.



Be careful when you’re looking to authenticate a gemstone. Know that two gems can overlap in both clarity and color. Sometimes more in-depth knowledge is required before you can properly separate man-made gemstones from their natural counterparts. Awareness of the different types of inclusions and their significance also helps.

Our laboratory also makes use of advanced instruments for tasks that go beyond microscopy or standard gemological tests. We use spectrometry based instruments for the detection and separation of natural diamonds against lab-grown (man-made) diamonds, which are also composed of pure carbon, with identical properties like hardness, luster and brilliance.