Ruby is the most valuable variety of the corundum mineral species together with sapphire. 

In its purest form, the mineral corundum is colorless. Trace elements that become part of the mineral’s crystal structure cause variations in its color. Chromium is the trace element that causes ruby’s red, which ranges from an orangy red to a purplish red.

Ruby gems

Boghossian’s Kissing Diamond ring with Ruby – Stephen Webster’s Hammerhead bangle

Ruby gem 

Elle Fanning at Cannes Film Festival – Chopard’s Red Carpet Collection

5 Facts


  1. Many cultures have long considered ruby a stone of kings for its beauty.
  2. Ruby is one of the traditional cardinal gems, together with amethyst, sapphire, emerald and diamond.
  3. The word ruby comes from ruber,  meaning red in Latin. In the ancient language of Sanskrit, ruby is called ratnaraj, or “king of precious stones.”
  4. Ruby is the traditional birthstone for July. Given as a gift, ruby is a symbol of passion and love.
  5. Not surprisingly, ruby symbolism and lore have many associations with power and wealth.

Rough, Cut & Carat Weight


The most common shape is a flat tubolar hexagonal shape, but there are elongated crystal from some sources.

In order to make the most of the rough shapes, the most common cut are oval and cushion.
Round, triangular, emerald-cut, pear and marquise shapes are rarer in larger sizes with high quality due to the rough shape.

Ruby presents pleochroism which is the appearance of different colors in different directions. It appears as red to purplish red in one direction and orangy red in the other.

High quality rubies over one carat are rare. The price per carat increases significantly for ruby as it is more important in carat. The Jubilee Ruby weighting 15.99ct is the most expensive coloured gem ever sold at auction in the USA. Sold for $14.2 million at Christie’s New York in 2016.

Clarity & Color


Color, without any doubt, is the most significant factor conditioning a Ruby‘s value. The finest ruby has pure, vibrant red to slightly purplish red color. In the trade the vivid red, slightly purplish or pinkish red rubies are called “Pigeon’s blood”, which is particularly rare in good clarity and bigger stones.

People in the trade also use to attribute a specific source to a ruby just observing its color. Even if a peculiar source such as Burma can give fine Pigeon’s blood quality rubies, other localities can produce very similar gems. 

Apprecieted color saturation goes from medium to deep intense range.
However the most desirable combination of color, hue and saturation is the one that makes you fall in love with!

Inclusion-free rubies are practically nonexistent, the gem value therefore depends on the visibility of its inclusions.
Some inclusions can actually contribute positivity to a gem’s appearance, for instance futile silk can give light and softness to the color.



Never tired to repeat, when you purchase gemstones and jewelry, TRUST is a fundamental factor. Trust goes from the seller, platform (if buying online) to the gem lab.

Ruby‘s price varies a lot also depending on its origin. You can imagine then the extreme importance of a gem lab certificate attesting the stone you are going to buy is effectively coming from a specific location. I guess you prefer to buy the proper value for your money, don’t you?

Dalila Daffara