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.

What is fracture filling? Well, some gemstones tend to be found with more inclusions or fractures compared to other kinds. Emerald is one of these gemstones, and it is usually very highly included with cracks, minerals, internal debris and all sorts of things. Many traders, in the efforts to improve emerald's transparency, subject the stone to some sort of filling- usually the material used is either oil, natural resins, artificial resins or proprietary polymers. Oil is the oldest and one of the most common substances used, therefore many in the jewelry business readily recognise the term- oiled emerald.

If your emerald is oiled, and you're not quite familiar with what this means, don't fret. Oiling is a very common practice for emerald, as a type of fracture-filling procedure. Over 90% of gem-quality emeralds are estimated to undergo some form of filling procedure in today's markets. A premium price point does exist for emeralds that are untreated though.



Oils and other filling substances have a refractive index closer to that of the surrounding emerald's, and this makes fractures less visible to the eye, nearly concealing them at times, and making a stone look more clear and beautiful than it originally was. In the above-image you can see the before-and-after shots of an emerald that underwent a fracture-filling treatment (although a proprietary filler was used for this stone, oiled emeralds would essentially look similar in terms of the general effect that improves apparent clarity).

Oils can gradually seep or 'sweat' out of emeralds over long periods of time (years usually). Heat or excessive light exposure can also hasten the oil leaving an emerald's fractures. The process can be re-done again though, by an experienced gem treater. Some substances, especially proprietary fillers made by branded companies, have a warranty that fillers can be removed without any damage to the stone, and then re-done easily. Not all though allow for this, and occasionally you will see some emeralds with residue of stuck-fillers nestled between cracks and fissures in the stone.

Depending on the degree of fracture-filling, many emeralds may require special care in cleaning. Ultrasonic or steam cleaners may not be advisable for heavily fractured emeralds or for stones that were treated in significant areas.

Well today let's take a look at a handful of faceting styles and shapes that have captured the market's attention for best displaying the appeal and beauty of a gemstone. First off, probably the most utilized cut for rubies and sapphires (non-melee) would be the oval mixed-cut. The mixed faceting style simply refers to a gem that has both the brilliant-cut faceting style (triangular & kite shaped facets) and the step-cut faceting style (four sided facets). One might be on the crown, the other may be on the pavilion, or the reverse can also be true. This particular cutting style allows gem cutters to save weight from the original crystal, by cutting with a bit more bulge, especially if cutting the pavilion as a step-cut. Unlike diamond, the focus for colored gemstones is more about the intensity of color, and adding more material intensifies the selective absorption process that expresses a stone's color to our eyes. (Image credits to Sotheby's Auction House)

While rubies and sapphires are very often cut as mixed cuts, another very popular cutting orientation would be what the industry calls the 'Emerald Cut', which as you might have guessed, is very popularly used with emeralds. This is mainly because of how emerald crystals grow. Compared to the common tabular shapes of rough ruby, emerald crystals tend to grow as hexagonal prisms, or at least in elongated formats. The Emerald cut is a rectangular step-cut style that makes use of bevelled edges, and it's been the number one choice for emerald gemstones for a long time now. Even diamonds have adopted the appeal of this cut, because it accentuates their transparency and clarity, while presenting a very bold elegance and feel.



While the two styles above are probably the most popular choices for colored stone cuts today, another forerunner would be the cushion cut. Now the cushion cut is a little less defined than the previous two we mentioned. There are square cushions and rectangular cushions, as well as other shapes and varieties. The main difference between the cushion cut and other cuts, lies in the fact that cushion cuts have curving edges on all sides when seen face-up. It sort of resembles a pillow, or a cushion in shape outline- hence the name. This cutting preference allows a good amount of weight to be saved, and just like the standard oval mixed-cut, this appeals well for gem-cutters due to the fact that color can be better shown with more material.

Colored diamonds are also often cut into cushion shapes. The 'oval' or 'stadard' cushion cut pink diamond, pictured below, is a prime example of this. Color will always be one of the defining factors in gemstone valuation- whether it be the presence of it or the absence of it.



Each gemstone can be cut in a huge variety of choices. Emeralds can also be cut as mixed-cuts, and star rubies & sapphires can be polished into cabochon cuts. There are so many choices for gemstone appearances in today's trade, that the main factor to consider is your own personal preference. Brilliant faceting styles create sharper, more crisp brilliance patterns, while step-cut faceting styles can save more weight, and deepen color. Proportions and angles are also equally important so as not to create areas of windowing or extinction, where light can leak out of the stone rather than bounce back to the viewer's eye.

Another large diamond that had recently been sold at auction, was the 163-Carat D-Flawless "De Grisogono". The gemstone was set at the heart of an asymmetrical necklace adorned by suites of emeralds and other diamonds.



The design by De Grisogono founder Fawaz Gruosi, prioritizes the full visibility of the gemstones' magnificence, and therefore strives to hide all metal from its facade. This almost invisible way of craftsmanship truly brings out the vivid brilliance of both the record-breaking stone, and its accent gems.



Documentations have shown that this one-of-a-kind masterpiece required a schedule of over 1,700 hours to complete. Fourteen craftsmen contributed to the piece's creation, and this is evident in the complexity of its structure and beguiling appearance.

The De Grisogono diamond and its host necklace, sold for 33.7 million US dollars in Geneva under the efforts of Christie's auction house and its partners.

While this number may strike some as being incredibly extravagant for a single piece of jewelry, it was actually viewed as disappointing for many veterans in the diamond auction industry.



Both diamonds and emeralds are favorites here within the jewelry circles of Metro Manila, however specimens even a fifth of the De Grisogono's carat weight are an incredibly rare sight inside Philippine jewelry boutiques. Practicality and trend both play a part in the country's demand for diamonds. Normally, one to five carat sizes are the prime picks for most high society Filipinos, due to their high-movability translating to a better investment value.



Above are pictures of both the diamond and its original rough form. Large diamond rough is very rare, so diamond cutters need to use an array of advanced instrumentation to scan and plot the best angles for cutting out the gem. The more weight preserved, the higher the returns will be for specimens such as this one. (Photography Credits to Christie's Auctions, and De Grisogono)