Ruby Gemstones

History

Rubies are one of the most expensive and sought after of all gems.  Rubies have been loved for thousands of years.  In ancient India, stories circulated that God created the Ruby and then created men to own it.  The Emperor of India loved Rubies so much that whenever a spectacular Ruby crystal was found, the emperor sent out his notable men to meet the precious gemstone on the way from the mine and welcome it in appropriate style.  According to The Bible a Ruby was the chief stone in Aaron's Breastplate and the stone of Judah. Because Israel's king came from Judah, the ruby came to be associated with royalty. Through out history Christian leaders have worn Rubies, even Martin Luther supposedly used a gold ring set with a Ruby as a betrothal ring.

Many of  the worlds most famous Crown Jewels are set with spectacular Rubies weighing hundreds of carats.  However mistakes have been made in the identification of some of these gems.  Two of the most notable are  The "Black Prince Ruby"  and "Timur Ruby" decorating the British Crown Jewels. These are actually Spinels not Rubies.

Prior to the 20th century, Rubies were considered more valuable than Diamonds, and in the mid-16th century a fine Ruby was priced at 8 times more valuable than a comparable Diamond.   Today an exceptionally fine Ruby of 3 carats or more will still command a higher price then a Diamond of the same size.

Famous Rubies

The Mandalay Ruby
This 48.019-carat cushion-shaped ruby was offered for sale by Sotheby's New York on October 18th, 1988 but received no bids.  Current asking price......15 million.

Alan Caplan Ruby
Known variously as the Alan Caplan Ruby or the Mogok Ruby, this 15.97-carat untreated Burmese stone was sold by Sotheby's of New York in October 18th, 1988 for $3,630,000; a whopping $227,301 per carat. It was purchased by Graff of London, who then sold it to the Sultan of Brunei as an engagement ring for one of his wives.

The Rosser Reeves Ruby
Weighing 138.7 carats, the Rosser Reeves Ruby is one of the world's largest and finest star rubies. Mr. Reeves carried it around in his pocket as a lucky stone, referring to it as his baby. The advertising mogul donated the piece to the Smithsonian in 1965.

What to look for when buying a Ruby

With Rubies COLOR is everything!

Rubies come in all shades of red and reddish pink. The most valued color is pure red with a hint of blue, known as "pigeon's blood" red. As corundum (aluminum oxide), rubies and sapphires are from the same family. All red corundum is classified as ruby, and all other colors are considered Sapphires. The red coloring in Rubies comes from the presence of chromium, and the occasional brownish hues come from the presence of iron.

Most Experts agree that a Ruby should have a medium, to medium dark, red color tone. Lighter gems should be classified as Pink Sapphire. However there has never been any agreement on exactly where the line is to be drawn. There is an old joke about questionable stones goes: "Whether it's a Ruby or a Pink Sapphire depends on whether you're the buyer or the seller."  Pink Sapphires has considerably less value then Rubies. 

Heat treatment and diffusion treatment 
Nearly all rubies on the market are treated in some way. Non-treated gems are available but you will pay a very high premium for those stones. 

Heat Treatment
In some cases, heat treatment will improve the depth of color because heat causes dissolution of inclusions and diffusion of impurities) into the surrounding corundum. Because fine inclusions cause some stones to look cloudy, heat treatment that dissolves the inclusions may also improve the clarity of the stone.
Heat treatment may also eve out the color in a stone or remove patches of color. Heating allows the color-causing impurities to more evenly distribute through the crystal.

How do you tell if a stone has been heat treated?
Detection of heat and diffusion treatment is possible because these treatments modify natural inclusions. This may involve rupture of gas or fluid inclusions or partial dissolution of mineral inclusions. For gems that contained needles, the needle margins may become diffuse.

Diffusion treatment.
 Significant color enhancement can be achieved through addition of the color-causing impurity to the surface of the faceted gemstone. For Rubies, this involves heating the stone to very close to its melting point in the presence of a chromium source. Chromium enters into the structure of the Ruby and diffuses into the Ruby. This is a slow process, so chromium enrichment only occurs in the surface layer. This is sufficient to produce a strong color enhancement that is difficult to detect by eye.

How do you tell if a stone has been diffusion treated?
There are several ways you can determine if your stone has been treated. Diffusion treatment will result in concentration of color at facet junctions, and will modify the refractive index of the gemstone.
An excellent, simple, non-destructive test for Diffusions is as follows:
Place the faceted gem in methylene iodide. If the gem has been treated the color will concentrate at the facets where the gemstone is thinnest.

          Nice transparent Ruby       

7.05 ct. Ruby with inclusions.  Worth well over $1,000.00.

Clarity:
Unlike other gems, inclusions or flaws in Rubies are a good thing. : Inclusions within a ruby are something like the gemstones fingerprints, stating its individuality while at the same time proving its genuineness like a certificate provided by Nature.  Inclusions do not affect the quality of a Ruby, unless they decrease the transparency of the stone or are located right in the center of the gem. While many cut rubies contain inclusions, gems that have many visible inclusions are less desirable than "eye-clean" stones. "Eye Clean" means flaws can not been seen with the unaided eye.  In some cases, inclusions such as fissures and cracks can make the stone more vulnerable to breakage. Gems with bad cracks should be passed by.

Cut:
All facets should be placed symmetrically. Facets should be smooth without pits or lines. All facets should meet correctly with out any waviness. 
The pavilion, or the bottom, of the stone should be a sufficient depth that you see bright reflections across the entire face of the stone. Shallow cut stones leak light and are not as brilliant as well cut gems. Undesirable "windowing," this is when you can see right through the stone, like through a window.
A well cut stone should be fiery with lots of sparkle and flash.

Cost:
There is a huge price range for Rubies.  Small Rubies can be easily found of $1.00 or less.  Large specimens with exceptional color and clarity can easily run into the tens of thousands of dollars.

Care:
Rubies are a hearty gem and can be worn everyday.  Shape blows should be avoided as they can chip or crack the gem. Rubies can be cleaned with just warm soapy water and a soft brush or in an ultra sonic machine.  Rubies should be stored so they do not come in contact with other gems.  Rubies will scratch any gem that is not a Diamond.

      Excellent 2.10 ct. Ruby      

The Best
The most desirable Rubies currently come from the Mogok mines in the North of Myanmar. This area was once called Burma and Rubies mined in that area still bear that name. Gems from this mine are often not treated in any way.  These gems are scares and are extremely valuable. 

The next most desirable Rubies come from the city of Mong Hsu in the North-East of Myanmar.  They mostly offer heat-treated Rubies in commercial qualities and sizes between 0.5 and 3 carats.  All Rubies from this mine are heat treated to remove undesirable purple coloring.

Good
Viet Nam, these display a slightly purplish hue
Thailand, often dark red tending towards brown and elegantly modulated deep red.
Ceylon-Rubies, were mainly light red, like ripe raspberries
East Africa, remarkably beautiful color, which may vary from light to dark red

Fair
Northern Pakistan in the Hunza-Valley, Cashmere, Tadchikistan, Laos, Nepal, and Afghanistan.
India, has relatively large Ruby crystals unfortunately these are full of inclusions.

Natural Vs Man made
The first synthetic rubies appeared on the market in 1908. Many people are surprised to fined out that Great Grandma's Ruby Ring is really a fake.
A man made gem will never have the value of a natural mined from the Earth gem. Weather to buy a natural or man made stone is a matter of personal choice and what one can afford to spend.  However you should buy a natural gem if you can.  Unfortunately there are many unscrupulous sellers who will try to sell you a man made ruby as a natural Ruby.  Here is what to look for. 

Natural origin may be proved by

inclusions (e.g., natural gaseous and fluid bubbles)

spectroscopic measurements.

Synthetic origin may be indicated by 

• the presence of flux inclusions and non-natural gas inclusions
• synthetic corundum may contain a visible seed crystal (esp. in older gems)
• wispy white veils
• strain cracks
• color looks too good or gem is too prefect.

Synthetic Ruby

Other Ruby information

Ruby is the birthstone for the month of July.

Healing Properties:
Ruby encourages the wearer to follow his or heart. The ruby reminds us of our soul's truth and helps us manifest that reality. It opens the heart and helps us stay in our own personal integrity. It has been called "the stone of nobility" which helps you in negotiations and it will shield you from negativity of all forms.  Rubies are considered good luck.

Science - the first lasers were made from artificial ruby crystals. They still are used for this purpose although other materials offer improved efficiency.

VARIETY INFORMATION:

• VARIETY OF: Corundum , Al2O3 .
• USES: Gemstone. 
•  BIRTHSTONE FOR: July
• COLOR: various shades of red. 
•  INDEX OF REFRACTION: 1.76 - 1.78
• BIREFRINGENCE: 0.009
• HARDNESS: 9
• CLEAVAGE: none, although there is a rhombic parting
• CRYSTAL SYSTEM: trigonal
• PLEOCHROIC: strongly