R7542 | medium | play | left | “Stone ID: R7542 – Weight: 1.72 Carats – Origin: Vietnam”Vietnam is a source of marble-hosted rubies, including the most common characteristics:
– Colors ranging from red to a more purple-pink color.
– Diffused light from clarity characteristics.
– High fluorescence.
They share characteristics with the rubies from Burma, though fine and untreated material is even rarer here. Most material is only cabochan grade and not facet-grade, though locals have interest in the low-quality material to make gemstone paintings and carve items related to phong thuy (like a Vietnamese version of feng shui).
Be aware that gem laboratories struggle to identify every gem specimen they look at, with many internally noted to be indeterminate. This is because not every ruby shows distinctive properties relating to origin, though every specimen is unique with their inclusions. Issues with origin ultimately relate to how these gems formed in the earth’s crust, where they end up deposited, and moved around (think earthquakes, floods, volcanic eruptions, etc). As an example; a group of rubies form from the same super-heated mixture of elements, but part of the deposit ends up being washed out of the bedrock by a river to somewhere else over the course of thousands of years. The only difference between the deposit found downstream in that river, and the original deposit upstream could be an impermanent country border. In this case, the country of origin cannot be distinguished between these rubies since they are from the same original deposit.
The border along Thailand and Cambodia is a very good example of this since there are a number of gem deposits other than rubies in the area, with the border moving back and forth for over a hundred years.
Printed lab reports all have disclaimers about gem origin, and certain other factors like the gem picture not being completely accurate (some labs are worse about this than others). However, the educated guess of a gemological professional with access to proper data bases, equipment, and experience, is much better than that of anyone without these resources.
While Vietnam was documented to have gemstones, serious mining efforts did not begin until after the Vietnam war in the late 1980’s. The discovery of alluvial deposits in the Luc Yen district brought a wave of interest from locals. It is important to highlight that these deposits are alluvial, since having the gems already freed from their host rock makes extraction much cheaper over a primary deposit, where the gem has to be removed from the host rocks. This also makes it possible that the only excavation tools needed are basic hand tools and a basket to rinse gem gravel in.
When more discoveries of profitable alluvial deposits were made, international interest came and Vietnam began its own gem rush. Another set of problems came along too like security and safety issues with the small, independant mines. There were attempts to modernize, but the remnants of war and decades of communist regime left the country in poor shape to do so at the outset of the mining rush.
Most of the large-scale operations have come and gone, though there are small pockets of rubies and other gemstones that are being worked by the locals.
Sources: Pham Van Long, Vincent Pardieu, and Gaston Giuliani. “Update on Gemstone Mining in Luc Yen, Vietnam.” Gems & Gemology, Winter 2013, Vol. 49, No. 4