The Mystery behind Pigeon’s Blood Red Rubies
The whole world, as we experience it visually, comes to us through the mystic realm of color. — Hans Hoffman
Color can seem to be the most intuitive concept, but what lies underneath the surface of a layman’s definition is a complicated web of optical phenomena. And, ever since the time humans have decided to pursue the colossal task of standardizing color schemes, matters have only been further puzzling. Read this article to learn about how popular Gem-labs used a combination of Science and Beauty to homogenize the definition of the ever famous ‘Pigeon’s Blood Red Rubies’ and why its important.
When we enter the gemstone markets, one thing that becomes clear instantaneously is the importance of color on the valuation of various beloved gem species. Each gemstone has a set of hues considered more desirable than others. One term you will often come across for describing a popular hue of the alluring rubies is, “Pigeon’s Blood Red”.
The color, as its name suggests, comes from its comparison to the iris of a white pigeon’s eye.
Though the origin of this terminology is purely trade-related, to serve the customers with comfort and reliability many gem laboratories have tried to put standardized criteria into place to reach the maximum degree of accuracy in defining the color.
Before we begin to explore the legend of the ‘Pigeon’s Blood Red’ Rubies, one thing that must be kept in mind while reading this article is that the above-mentioned term does not apply to every Ruby exhibiting the stated criteria. Gem Laboratories have varied opinions on the acceptability of color-enhancing treatments to grant the following label. One agreed-upon conscience is that the term is reserved only for natural rubies.
Now, the first among all Gem Labs that pursued the task of denoting some Rubies the title of ‘Pigeon’s Blood Red’ with their certification was The GemResearch Laboratory (GRS). They wrote a set of parameters in 2015 for distinguishing the Rubies of Pigeon’s Blood type, as listed below.
- The gem must have a vivid red hue (free of brown tones). The color is compared with the stones from the GRS master set in broad daylight.
- Rubies must exhibit medium to strong fluorescence in long-wave UV.
- Rubies must have high chromium (Cr) of approx. 0.3 to 0.5 wt-% (or higher) and very low to medium iron (Fe), while the ratio of Cr/Fe must be greater than 1.
- GRS will reject all synthetic, diffusion treated, lead-glass treated, or heat-treated gemstones from obtaining the label.
In the March 2017 GAHK Seminar, Dr. Michael S. Krzemnicki from SSEF made a presentation titled “Pigeon blood red & Royal blue: Working towards an international standard”. He conferred parameters for the classification of Pigeon’s Blood Rubies according to SSEF and Gubelin Gem Lab. The same three criteria given by GRS with a few additions were stated.
- Rubies must show strong saturation and vivid red hue. The color is compared with the stones from the master set under a standardized light, ideally continuum. The color of the Ruby must be observed from the top and must be tilted 20° in all directions.
- Rubies must show minimal or no color zoning.
- Rubies must be relatively free of eye-visible and dark inclusions.
- Rubies must show vivid internal reflections.
- The gemstone must be natural and untreated.
Originally the term ‘Pigeon’s Blood Rubies’ was used only for the finest Rubies from Mogok, Burma.
In recent years it has been used to describe Rubies from several countries including Vietnam, Tajikistan, Afghanistan, Madagascar, and Mozambique. This creates a detour from the emphasis on the origin and gives a fair opportunity for Rubies from different geographical localities to enter into the gem trade on the basis of their beauty.
While this may give you a hint when you come across a Ruby marketed as ‘Pigeon’s Blood red’, you must not break the bank on it unless it is accompanied by a renowned gem laboratory’s report stating a similar opinion.
If the beauty of these rubies enticed you, browse through an exclusive collection of such certified ‘Pigeon’s Blood Red Rubies’ here: Pigeon Blood Red Rubies — The StarRuby Shop.
References and Further Reading:
- https://www.ssef.ch/wp-content/uploads/2018/01/SSEF_Pigeonblood_Royalblue_Criteria_2017_HK.pdf
- http://gemresearch.ch/grs-mozambique-pb-reports/
- http://gemresearch.ch/an-ethical-debate-concerning-pigeons-blood-and-royal-blue-for-corundum-from-diverse-origins/
- Hughes, R. (2017). Ruby & Sapphire: a gemologists guide. s.l.: Bangkok
