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Roger Weller, geology instructor

by Paige Wakatani
Physical Geology
Fall 2016

Rubies: Not Just For Slippers


Ruby Slippers

Rubies are an amazing gem. They are bright red and beautiful. For those born in July, like myself, they are a symbol of their birth, called birthstones.  As shown in the picture above, rubies have been used for slippers in Oz, or to commemorate the anniversary of the Wizard of Oz movie.  Rubies make wonderful necklaces, rings, bracelets, and are even featured in some royal jewelry.  Ruby color can range from a light red to a dark red.  They can even have hints of blue, orange, pink, purple, or even fluorescence to them.  Rubies are one of, if not the most, beautiful gem stones found on earth.

Untreated and Heat-treated Rubies


Real Rubies:

Diamonds may be a girl’s best friend, but rubies are far superior.  Rubies are the second hardest material, next to the diamond.  Rubies have so many more variations.  There are natural rubies and synthetic.  Natural rubies come in dozens of variations as well.  There are Burmese, Thai, Tanzania, and many more rubies. Synthetic have three types: doublets, verneuil or flame fusion, and flux grown.  Star rubies are a very popular type of ruby. This ruby is easily seen by its star on the front. It is also an inspiration for a group from a popular comic book company.

Image result for burmese rubies

The Burmese rubies are one of the highest quality rubies.  The most sought-after Burmese rubies have a deep red, because of the chromium, and sometimes a hint of blue or pink.  These rubies only come from specific regions.  For example, two regions are Burma and Mandalay.  Rubies all have blemishes.  Without blemishes, the ruby is not natural.  Burmese rubies have the least amount of blemishes out of all types.

Image result for thai rubies

Thai rubies are second, just behind Burmese rubies. They normally have darker undertones due to the iron and chromium mix.  Thai rubies may also have hints of brown and burgundy.  These rubies come from an area southeast of Bangkok.

Image result for Tanzania rubies

Tanzania Rubies are found in deposits near Songea.  These rubies have a color that somewhat resembles a garnet.  They resemble garnets so closely that even jewelers are often confused by their closeness.  The intensity of Tanzania rubies color diminishes along with size.  With this, Tanzania rubies become much more valuable the smaller they become.

Image result for madagascar ruby

Madagascar rubies are another high quality ruby. They are, however, relatively new to the ruby market. The mines in Madagascar are in the Andilamena and Vatomandry regions.  Rubies can be found in a wide variety of igneous rocks there.  Each area creates rubies with differences.  Andilamena rubies are best when given heat treatments.  Vatomandry are the opposite.  Vatomandry rubies have orange, red, and pink highlights.

Image result for afghan ruby

Rubies have been mined in Afghanistan as far back as the very first century.  Badakshan and Jagdalek regions have the ruby mines in them. Not much is known about the Badakshan rubies.  The Jagdalek rubies, however, have more information.  These rubies are produced with color ranging from faint to deep red. These rubies have qualities not found anywhere else.  They can also have a purple tint or fluorescent shine to them.

Image result for indian ruby

Indian rubies come from the Karur-Kangayam and Hole-Marsipur belts, located in the southern Indian states of Tamil Nadu and Karnataka.  These regions are also famous for sapphires, moonstones, iolites, aquamarines, garnets, sunstone, and corundum.  Karur, a city in India, is well known for their rubies.  Channapatna, near Madikeri, is famous for its star rubies.  Subramaniam, also known as the Red Hills, is where rubies can also be found.

Afghanistan ruby 

Synthetic Rubies:

Synthetic, or man made, rubies usually have three types. The three types are: doublets, verneuil or flame fusion, and flux grown.


Doublets are not as fashionable nowadays, but they make great gifts.  Doublets normally are stones with imitation backings with a natural corundum crown. The crown is normally made of green or white corundum.  If a person looks carefully at the gem, the glue is very noticeable.


Verneuil or flame fusion is attributed to the process of production.  They are easily distinct from actual rubies.  These rubies are characterized by certain curved color banding called atriae.


Flux grown rubies are not easily seen as different from real rubies.  Molten flux is crystallized in certain temperatures and pressures to create flux grown rubies. These stones may have fractures when pressure is released.  Different flux processes produce different rubies.  Most often, the flux grown ruby looks like a real ruby.


The most valuable type of synthetic ruby is the flux grown.  It is, as previously stated, almost indistinguishable from natural rubies.  This makes it the best to use as gift jewelry.  It is less expensive than a natural ruby, but it is more realistic than other synthetic rubies.


The Star Effect  


Star (Sapphire) Rubies:


Star rubies are a popular type of ruby.  They can be identified by their pleochroism.  Pleochroism is when the color varies based on the viewing angle. The star, which has six rays, shimmers best on the surface in sun light.  These rubies will be fluorescent in long or short wave ultraviolet light. This property is often used to help in identifying a stone and the geographical place of origin.  Star rubies can be red, pink-red, or violet-red.  They are a nine on the Mohs scale.  They can be transparent, translucent, or opaque.  They can also be anywhere from vitreous or silky in luster.


Star rubies are perfect for wonderful gift jewelry, as each star ruby has its own star and can shiny and glow differently based on each gem stone.  These rubies make wonderful rings and necklaces.


Image result for star sapphire corps symbol


Star rubies are also popular in the world of comic books. They are the inspiration for the Star Sapphire Corps in the DC comics’ Green Lantern comic books.  As shown in the picture above, the star ruby was used to inspire the symbol of the Star Sapphire Corps, or the Violet Lantern Corps.




Pictures -Rubies -Synthetic -Star Sapphire -Slippers -Burmese -Thai -Tanzania -Madagascar -Afghan -Star Sapphire Corps