Rubies & Sapphires

Both Rubies and Sapphires fall under the same family known as “Corundum”- both are just a combination of aluminium and oxygen.  Sapphires come in every colour imaginable – green, blue, black, orange, pink, brown, grey, yellow, purple and can even be colourless; sometimes they come even bicoloured. In gemmology sapphires are always termed with their colour, for example blue

sapphire, yellow sapphire etc…  The Rubies on the other hand come in various shades of red.

Ruby & Diamond on Gold 14 Ct. Ring

Both Rubies and Sapphires were considered as regal gems worn by kings and queens; in Catholic religion sapphires have been used in the rings of bishops and cardinals – it is said that the blue colour of sapphires symbolises heaven and supposedly, people who wear sapphires become more virtuous, devout and wise. Buddhists believed that sapphires signified friendship and steadfastness. Ancient Hindus thought that if they offered a Ruby to the god Krishna, they would be reborn as an emperor. According to Hindu writings, the Ruby represented the sun and the Sapphire represented the planet Saturn.

Generally, when sizes of a carat or more, both Rubies and Sapphires usually have either an oval or antique cushion shape style – both these styles allow the cutters of these gems to save the most weight of the original rough. However when rough crystals have other shapes like triangles, kites , shields, pears, heart etc they can be cut in these fancy forms as well. The connoisseurs of these gems know that Rubies and Sapphires are often not as symmetrical as that of less expensive coloured stones. That is because cutters know a lot of money can be lost when Rubies and Sapphires are cut down to symmetrical shapes.

Sapphire & Diamond on Gold 14 Ct. Earrings

In the smaller sizes, say less than half a crat, Rubies and Sapphires are nowadays commonly cut into the traditional round, oval, pear, marquise, square, and rectangular shapes.  Before the 1300’s, gems were usually cut into unfaceted rounded beads or into cabochons (dome shaped stones). At that time Rubies and sapphires looked attractive cut into cabochon style.  At first, facets were added haphazardly, but by around the 1450, various styles evolved and by the 1920’s cutters arrived to the brilliant cut of precious stones. This brilliant cut was later also applied to Rubies and Sapphires.

One may ask how does the shape and cutting style affect the price of these gems. Actually, it is a combination of clarity, colour and brilliance which normally plays a greater role in determining the price of a Ruby or Sapphire, rather than the shape or cutting style. Nevertheless, these two factors can affect the value of these stones.

Since the cabochon is the simplest style, it costs less to cut than faceted styles. Another reason cabochons are priced less is that they are often made from material that is unsuitable for faceting. However, it is good to note that these two gems, cut into cabochons, can also be of a high quality, especially those found in antique jewellery.

Judging RUBY colour: 

First of all, those interested in buying these gems, must understand what “Hue” stands for in gemmological terms. “Hue” refers to a pure colour such as red, orange, or orangy red.  The “Tone” refers to the amount of colour present in the stone. The lightest possible stone is colourless, the darkest is black.  “Tone” stands for lightness/ darkness and can be termed as very light, light, medium light, medium dark, dark or very dark. The “Purity” describes the degree to which the hue is masked by brown or grey. Intensity, strength and saturation are the other works for colour purity.  In some certificates colour purity is termed as vivid (most pure), strong, moderately strong, very slightly brownish or greyish, slightly brownish or greyish, brownish or greyish (least pure).

 In order to evaluate Ruby colour, gem dealers agree that vivid colours are far more desirable than dull, muddy, brownish colours. To understand more, one must compare the colours of red garnets and rubies, side by side, and determine which one has the most vivid colour and the least amount of brown. Being aware of colour purity will increase your sensitivity to it and will help one to choose a more desirable Ruby. When judging the hue of a Ruby it is just as hard as judging the tone. The different tones and possible brownish tints are distracting. Moreover, remember that Rubies are a blend of two colours- purplish red and orangy red. When one looks at rubies from different directions while moving them, you can see these two colours. This is due to certain optical properties of corundum. When judging the hue, one must look for the dominant colour in the face up view. Generally, the more purple or orange a stone looks, the less it costs. Usually, Rubies have an orangy or purplish tint and this a matter of personal taste as to which is best. However, one has to note that to find a medium-dark, vivid red ruby is very difficult. We always advise clients to choose a colour that one finds attractive and that fits one’s budget. Keep in mind that colours seen in synthetic stones, paper, plastics and fabrics may not be found in a natural gemstone. However, comparison objects can help determine how purplish orangy or brownish a tone is and using them is more reliable than trusting one’s colour memory.

Now we pass to explain how lighting affects Ruby colour. Visualise how different the colours of a snow-capped mountain are at sunrise and at midday. This difference is due to the lighting, not to a change in the mountain itself. Likewise, the colour of a Ruby will change depending on the lighting conditions. For example, under fluorescent lights some Rubies have a neutral effect, others add a green, which can make red stones look greyish, orangy stones more orange, and purplish ones more purple. Under the sunlight, and depending on the time of day, the season of the year and the geographic location, Rubies will have their hue effected. No matter what is the hue of the rubies, these will look brighter and less black in the more direct, intense light of the mid-day, summer or tropical sun. Another effect of sunlight is that ultraviolet rays can cause a red fluorescent glow in Rubies, which also makes them look redder. Rubies from Burma are particularly noted for their strong red fluorescence.

Judging SAPPHIRE Colours:

Before the 1980’s jewellers did rarely sell Sapphires that were not blue. This was due to a large percentage of fancy Sapphires (non-blue Sapphires) were pale and unattractive. Later in the 1980’s some dealers in Thailand started to intensify the colour of fancy Sapphires with controlled heat treatments. Intense yellow Sapphires, in particular, became plentiful. Also, new sources of fancy Sapphires were found in countries like Tanzania. So today one can find pink, orange, purple, yellow or green sapphires in jewellery stores.

In gemmological terms when Sapphire is termed by itself, it refers to the blue variety. In its highest qualities, it is more expensive than the other Sapphire colours. Top quality Kasmir Sapphires, for example, are one of the most expensive stones to buy. Frequently, the best colour of sapphire is described as a cornflower blue. Most likely, your mental image of this colour is different than that which the jeweller has in stock. It must be noted that the cornflower (the actual flower) come in varying shades of blue and violet as well as pink, purple, white and yellow. Thus “cornflower blue” evokes a wide array of colour images even to people that have seen the flower. Since terms like “cornflower blue”, “inky blue” and “pigeon blood red” are very ambiguous, they are not normally used by gemmologists.

There are different opinions as to what is the best Sapphire hue. Some say blue; other say violetish blue. Most dealers agree, however, that greenish blue is less valuable. Dealers also have different tone preferences. Some prefer medium tones of blue. Others prefer medium-dark tones. The GIA in its coloured stone grading course describes the most expensive sapphire colour as either a medium-dark (vivid blue) or medium-dark (vivid violetish blue).  

When one refers to Padaradscha Sapphire this actually is a pinkish-orange stone found in Sri Lanka and is the rarest and most prized of the fancy sapphires. Its name is believed to have come from the Sinhalese word for the lotus flower, which has a similar colour. Frequently, orange sapphire is called “Padparadscha”, but most corundum dealers agree that both pink and orange hues must be present for a stone to be a true Padparadscha. Actually, this stone can range from a light to medium tone and from a pinkish orange to orange-pink hue. If the colours look a bit brownish, the value is greatly reduced, and the stone may lose its classification as a “Padparadscha”. It must be remembered that with all Sapphires, vivid colours are the most prized.

Pink Sapphires are next in line to Padparadscha. These colours are also highly prized of all fancy sapphires. Since pink is a synonym of light red and since fine Rubies cost more than Sapphires, many Asian dealers prefer to call pink Sapphire as Rubies. In the western world jewellers prefer to treat the pink sapphire as a unique stone with its own merits, rather than as a second-rate Ruby. High quality pink Sapphires are rarer than Rubies or blue Sapphires and can cost much more. In GIA coloured-stone grading charts, the most valuable pink Sapphires range in hue from vivid purple-red to reddish-purple and have medium -light tone. As the stone gets lighter, more brownish, or more purple their value decreases.

During the 1980’s there was a significant increase in the production of Orange Sapphire, thanks to expanded mining in Tanzania’s Umba River Valley. The orange sapphire ranges from a yellowish-orange hue to an orangy red. Vivid red-orange stone with medium-dark tones are the most valued. Whether a pink-orange Padparadscha or red-orange sapphire it is the supply, demand, and tradition more than logic which sets the prices for these stones.

Purple Sapphire is a step down in price from orange sapphire. The more red and less brown or grey a purple sapphire has the greater its value. Medium-dark, purple-red stones, which are sometimes called plum sapphires or amethystine sapphire are the most prized.

Yellow Sapphires are fairly common. These range in colour greenish yellow to orangy yellow. Strong light yellows or orangy yellows the most valued. The least valued are the very pale or brownish stones. When buying a yellow Sapphire, it is important to go more for the clarity since their high transparency reflect more visible blemishes in the stone. Prices for these stones are similar to those of purple sapphires.

Green Sapphire is the lowest-priced transparent gem quality sapphire. One of the reasons is that the green sapphire does not come in strong or vivid colours. Green sapphires range from a blue-green to yellow-green. Its most valuable colours are a slightly or very slightly bluish green of a medium-dark tone.

Having evaluated the various colours of sapphires, it does not matter which colour one chooses as long as it looks good when worn.

Judging Clarity:

Clarity is the degree to which a stone is free from external marks called blemishes or inclusions. Even though terms like “flaw” and “blemish” have negative connotations, their presence can many times be positive. Flaws are identifying marks that can help one to identify the stone. They can lower the price of a stone without affecting its beauty. They can also increase the value of a stone by helping prove that its origin is for example, from Burma or Kashmir (these places have a good reputation for producing top-quality stones). Flaws are especially important as evidence that the stone is natural. One must, however, avoid flaws that threaten the durability of the stone. Also, when a stone is viewed with the unaided eye, the flows must not mar its overall beauty. A professional jeweller can always help one make a choice that will suit both one’s needs and the budget.

Judging Cut:

Cut plays a major role in determining the value of Rubies and Sapphires because it affects their colour and clarity as well as their brilliance. For example, a stone that is cut too shallow can look pale and lifeless, and it can display flaws that would normally not be visible to the naked eye. When professional jewellers refer to the cut,  they would refer to it as the proportions of a stone (deep or shallow pavilion, off-centre culet) and the finish of a stone (polishing marks or smooth flowless surface, misshapen or symmetrical facets). In gemmological terms the shape of the stone (round or oval) and the cutting style (cabochon or faceted, single or full cut) do not refer to “CUT”. When stones have an obvious unsymmetrical shape or profile or a culet that is extremely off centre, or excessive depth, or lumpy, bulging pavilion, these will all have an effect on the grading of the “CUT” and professional jewellers would not have these in their stock as they avoid buying such stones. Gems which are in this poor cut category are usually bought at a much cheaper price.

Judging Brilliance:

When the term “brilliance” is applied to coloured stones, it means their ability to reflect light and colour back to the eye of the beholder. If a stone is brilliant it has “life”. If there is low brilliance or none at all then it is referred to as “dead”. Brilliance should not be confused with “glare” which is a pale or white reflection of light off the surface of the stone. To understand more about “brilliance” ask your jeweller to show you different cut stones and compare their brilliance under the same lighting conditions. This will help to develop the eye. Once you can recognise a fine-cut, brilliant stone, you’ll be well on your way to spotting value.

It must be remembered that finding an attractive stone, however, is more important than finding one at a bargain price. Rubies and Sapphires with lots of life and colour will always be valuable, but they may not always readily available.

Caring for your Sapphire and Ruby Jewellery:

It’s not a coincidence that the ruby and the Sapphire are the most popular coloured stones for everyday wear.  Their hardness, toughness and resistance to chemicals make them ideal jewellery pieces. Though these two stones can resist ultrasonic cleaning, yet it is very risky to do it on a regular basis. I would advise not to  be cleaned at all under the ultrasonic or steam cleaner. Best is to simply soak and wash it in warm sudsy water using a mild liquid detergent. Then dry it with a soft, lint-free cloth. No matter how dirty the stones might be, never boil them because they may create cracks or a change in colour. Also, never soak them in any solution containing borax as this may cause the surface of the stones to corrode.  Jewellery pieces should be wrapped separately in soft material or placed individually in pouches or the padded jewellery bags. If a piece is placed next to or on top of other jewellery, the metal mountings or the stone can get scratched. Occasionally check your jewellery for loose stones. Shake it or tap it lightly with your fingers while holding it next to your ear. If the stones rattle or click, have a jeweller tighten the prongs.

I hope that by reading this article a prospective buyer would gain more confidence to make an intelligent choice when buying Rubies and Sapphires. Beware of sales or advertisements that seem too good to be true; if possible, establish a relationship with a renowned jeweller that you can trust and who looks after your interests; he can help you find buys which you would not find on your own. Finally,  choosing a gemstone is a very personal matter and it would always help to talk to jewellery professionals to gain more faith in your intuitions and in your ability to learn to evaluate gems. After all, when it comes to selecting a Ruby or Sapphire, you’re the one who knows what’s best for you.