Pigeon's Blood Red Rubies

Royal Blue Sapphires

Trade Colours

For many centuries, gemstone traders have been using certain terms to describe the outstanding colours of some specific gemstones. These “trade colour terms” are used by the majority of people in the gem trade for a certain quality of gemstones, mainly describing a certain hue, but also implying other quality criteria, such as transparency, size or the presence or absence of treatments.

Although the trade colour terms are well known and commonly used within the international trade, their are often slight variations in the interpretation of these terms. In addition, geographical variations as well as historical evolutions have to be considered.

Since almost 80 years, the Gubelin Gem Lab is studying the history and closely observing the evolution of such trade colour terms. After having conducted considerable research in the mining areas, among traders and in the historical literature, the Gubelin Gem Lab now established a consistent definition of several trade colour terms for corundum, and has defined stringent criteria and procedures to allow an accurate determination of these colours. These procedures exclude any ambiguity related to the use of these terms and ensure the standard of integrity the Gubelin Gem Lab is known for in the gemstone industry.

Beside the colour, which is analysed and checked for compliance with the Gubelin Gem Lab standards by several traditional and advanced techniques, additional decisive factors are taken into consideration to qualify for a “trade colour call”. These include the following:

Only natural unheated rubies and sapphires can qualify. Both faceted and polished stones can qualify as can also gems showing asterism, however, a high transparency is required. Indeed, also the weight is taken into consideration - rubies need a minimum weight of 1.00 ct to qualify, sapphires must weigh at least 3.00 ct.

Pigeon's Blood Red Rubies

„ ...asking to see the pigeon’s blood is like asking to see the face of God“

Of all the varieties of rubies the true pigeon’s blood red is the most precious and treasured – primarely  found in Mogok Valley, Burma. Extremely rare – more a colour of the mind than the material world.

Trying to put this fascinating red into words is a challenging task and even when succeeded the phrasing still leaves room for imagination and interpretation by both author and reader. Dr. Eduard Gubelin, described it with the following words:

“Ruby owes its personal popularity to the gorgeous glowing colour of smoldering red fire beneath its shining, lacquerlike surface, and its name, derived from the Latin word ruber = red, denotes the embodiment of the most beautiful red. Light and velvety shades range from pink to darkest purple, but the crown of all the beauty, the noblest and most precious nuance is pigeon blood red, a saturated shade of carmine red. The more glowing, the more vivid is the red sparkle, the choicer and more costly is the ruby.”

Many legends and myths exist on how and why this true red came to its name “pigeon’s blood”. From comparing it to the centre of a live pigeon’s eye over defining it as the red of the first two drops of blood from the nose of a freshly slain Burmese pigeon. The more scientific but of course much less mystic explanation is, that in attempt to seek a more quantitative description for this mysterious red James B. Nelson sought the help of London Zoo. Their Research Department were quick to oblige and sent a specimen of fresh, lysed, aerated, pigeon’s blood which was indeed the match to the colour of these unique rubies. (Journal of Gemmology, 1985, XIX / 7)

Royal Blue Sapphires

To possess a Royal Blue Sapphire is like being   
the keeper of „tears from the eyes of the goddess Saitya”
(The Color Treasury of Gemstones, Dr. E. Gubelin) 

As in the rich and sumptuous description of the blue sapphire colours to follow Dr. Eduard Gubelin endorses that the royal blue sapphires are among the most precious and coveted. Near to every shade of blue can be found in the world of sapphires – from dense, dark gentian blue to crystal-clear ice blue, from dancing, frivolous azure blue, though pale, cheerful sky blue to crackling, exciting electric blue.  One’s vocabulary seems too paltry to do justice to the many possible variants of blue. Though in spite of all these varieties of blue gems, one of the most treasured and sought-after is the enchanting beautiful royal blue sapphire – deep and luscious, as unfathomable as a mountain lake.

Many famous stones such as the Rockefeller Sapphire are of this intriguing shade of blue. The highest quality sapphires from the famous mines in Mogok, Burma, are typical representatives of the precious royal blue colour.