The return of Burmite amber

David Lamb (UK)

For fossil collectors, lapidaries and scientists, the reappearance of Burmite is major news. Burmite is the traditional name for the rare, Cretaceous amber mined in the Upper Hukawng Valley of northern Burma (Myanmar). It is the hardest, oldest and, in the opinion of many collectors, the most beautiful, gem-grade amber.

Most Cretaceous amber is very brittle and, therefore, unsuitable for use as a gemstone. Generally, amber gems are cut from younger and more plentiful types like the Baltic, Mexican and Dominican ambers. These ambers range in age from 25 to 50 million years old (Miocene to Eocene), whereas recent research has placed Burmite in the range of 110 million years old (Cretaceous).

This places Burmite in a very unique position as possibly the most desirable amber for both gem cutters and scientists. Early research had suggested a younger age for the Burmite but entomologists always suspected that the archaic insect inclusions they were seeing in it were much older. This view is now supported by the more recent research.

Asian amber is sometimes called “Hu Po” or “tiger’s soul” as, in the local mythology, when a tiger dies in the forest, its soul penetrates the earth and becomes a piece of amber. I believe this belief may have arisen as a result of the flow patterns observed in Burmite that sometimes resemble red stripes. In accordance with this legend, the amber was considered to have great significance and power and was used in medicines and magical charms.

There is also a written record of Burmite being used by Chinese craftsmen as early as the Han Dynasty (206 BC to 220 AD). Exquisite carvings in Burmite were a highly valued component of the annual tribute to the Chinese emperors. British explorers first visited the site of the Burmite mines around 1836. A confirmed specimen of Burmite purchased in 1860 from Guangzhou, China weighs an incredible 33.5lbs. With a diameter of 53cm, it is considered the largest known piece of transparent amber in the world and now resides at the Natural History Museum in London.

The Geological Survey of India reported that, for the years 1898 to 1940, over 82 metric tons of Burmite were mined with a yearly average of just under two metric tons. This may seem like a lot of amber but one has to put that in perspective. The “blue earth” of the massive Baltic deposit yields up to 1kg/m³. This amber-bearing layer is up to 10m thick giving a potential yield of 10 million kilos per square kilometre. The amber deposits of Burma are much smaller, contributing to its relative rarity.

During the Victorian age in England, Burmese amber became especially fashionable with two particular sub-types seen as the most desirable:

• A pure cherry-red variety. This is still in great demand, especially in Asia. While many pieces display various red shades and swirling red flow patterns, the cherry-red is a totally consistent color throughout the piece. This variety can be identified even in the rough by the unusually coloured outer crust and its ‘sandpapery’ feel. The normal pieces of ‘rough’ Burmite feel smooth by comparison. One theory is that these pieces may have been altered by forest fire sometime after their original deposition. Many of the large Burmite pieces have a disc shape, probably caused by the amber being eroded out of its’ original deposition site by running water and re-deposited (perhaps several times).
• “Root-amber”. This other rare variety of Burmite, which so attracted the Victorians, was described as “coffee-coloured resin with creamy swirls”. The wood-burl look and unusual colours caused people to incorrectly assume it had some relationship to the roots of the trees. The real cause is massive calcite intrusion after the amber was buried. Burmite nodules are often completely covered in calcite and cracks in the pieces are filled with it. The root amber contains a mix of Burmite and calcite and, being the same hardness, it takes an excellent polish.

Unfortunately, Burmite mining was completely disrupted by heavy fighting during WW2, especially along the Burma and Ledo roads. There are no records of Burmite yields after 1941 and this remarkable gemstone and palaeontological treasure was not seen in the West for over 50 years. It is believed that, during those years, small quantities were exported to China. In 1999, a Canadian mining concern, Leeward Capital, in concert with its Burmese partners, began importing Burmite.

One of Leeward Capital’s first major customers for the Burmite, which has proven to be a scientific treasure trove, was the American Museum of Natural History in New York. Since 2002, leading scientists have published dozens of new papers describing the unique specimens found in this fossil resin and many more such papers are pending. Discoveries have included the oldest representatives of bees, ants, grasshoppers and mosquitos in the fossil record.

The Burmite was deposited in an age when insects and flower species were proliferating, as were their interactions, and it provides an unprecedented window into this time. The very rare, Lebanese amber is presently the oldest known amber containing insect inclusions, at 125 million years. However, the somewhat younger Burmite, at 110 million years, is considered more important because of the greater biodiversity it contains. The resin that formed the Burmite was deposited in a tropical forest, the most bio-diverse ecosystem on the planet. The Lebanese resin was by contrast believed to come from a temperate forest with far fewer species.

The gem qualities of Burmite amber are just as impressive as its scientific credentials. I began cutting Burmite very soon after it was re-marketed in 2002. Though it is the hardest amber, Burmite is much softer than traditional gemstones and very easy to work with. I very quickly realised it was superior for gemstone use. Not only does it easily take a brilliant polish, but almost every piece is a new experience with the variations in the Burmite seemingly never-ending.

This amber is well known for the property of shifting color and shade according to the ambient light conditions. The red coloration of Burmite generally consists of small dots of red in a very golden resin. This causes the color to change and flow-lines to disappear and then reappear according to the angle the piece is viewed at. In some pieces, the flow lines are so complex, they look like picture agates. Burmite also fluoresces much more strongly than most other ambers under UV light and sometimes this shows even in strong sunlight.

I feel very privileged to be one of the first people to work with this treasure after so many years. For the collector, Burmite offers a good chance of finding a specimen not yet seen by science and, at worst, he or she will get a collection of stunning gemstones. Despite the limited availability of the Burmite, I believe the present price is unreasonably low. Should events disrupt production or demand rise, the price would likely show a lot of movement, potentially also making it a good investment.