Birmit

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About 150 km northwest of Myitkyina (capital of the province of Kachin; red point) is the discovery area in the Hukong Valley.

Birmit is the name for a fossil resin that is found on Eocene deposits, but was presumably rearranged and actually comes from the Upper Cretaceous (age: approx. 100 million years). Other names for this type of amber are Burmit, Burma amber, Burma amber. Otto Helm used the term Birmit in his first description .

Find area

The various names for this fossil resin go back to the area where it was found in Myanmar (formerly known as Burma or Burma, depending on the language area). The finds come from the area of ​​Mogaung and the Hukong Valley in the Kachin region in the north of the country and from the mountain ranges that form this valley. In 2015, another site was discovered near Hti-Lin in the Magwe region , which is much further south .

The amber is mainly found in near-surface formations of finely laminated blue sandstone or slate , which alternate with limestone layers and conglomerates . Occasional very thin layers of coal embedded in sandstone and slate also contain small amounts of amber.

The Portuguese Jesuit Alvarez Semedo was the first European to report on the discovery area in the Hukong Valley in 1613.

Features of the Birman

In the description of Otto Helm it says u. a .:

“Birmite [differs] from succinite , the actual Baltic amber, and from Romanite [...] because of the lack of succinic acid . From the other [...] resins from the group of retinalites , Birmit differs through its firm, coarse nature, [...] its chemical components, its often lively color tones and its [bluish] fluorescence [...] "

In addition, a green fluorescence was observed on some, mostly burgundy-red pieces. The pieces examined by Helm consisted of carbon (80%), hydrogen (11.5%), oxygen (8.4%) and traces of sulfur .

The Mohs' hardness of Birmit is 2.5 to 3.0, slightly higher than that of succinite. However, the information on the content of succinic acid varies.

The colors of the Birch range from dark brown to red to clear wine yellow.

Obtaining and using the birch

Birmit has been systematically promoted and traded for at least two thousand years. At the beginning of the 20th century, a few hundred small mines were still in operation, but only relatively small quantities could be extracted from them. In the period from 1897 to 1930, the total yield was only around 40 tons. According to other sources, a total of 83 tons of amber are said to have been mined between 1898 and 1940. In 1924 the production is said to have reached its highest level with around 4.5 tons. Despite this rather modest production volume compared to Baltic amber (around 500 tons per year), very large pieces were apparently not uncommon. In a report by the paleontologist Fritz Noetling from 1891, pieces larger than a head are mentioned. In the Natural History Museum (London) there is a deep red, transparent piece weighing 15 kg. After the military seized power in 1962, amber mining practically came to a standstill before resuming at the turn of the millennium. The mining is carried out by a Canadian company on the Noije Bum hill in the mountain ranges that border the Hukong Valley to the west, where the fossil resin is only shallow and is mined in open-cast mining. In the first few years (as of 2005), production was between 10 kg and 500 kg per year, depending on demand.

The easy-to-work fossil resin was already used by Chinese artisans during the Han Dynasty , around two thousand years ago. It is believed that most of the raw material was found in what is now Myanmar. It is also possible, however, that smaller deposits existed in the Chinese province of Yunnan , which is directly to the east of the actual find area and through which the Burmese trade route passed. Although Baltic amber came to China very early (one of the oldest records is a grave find from the early 11th century), which gradually ousted Birman, exports of Birman to China are documented until the middle of the 20th century. In the Chinese workshops, wonderful Buddha figures and animal figures as well as necklaces for mandarins have been made from Birmit amber.

In the 19th century, Mandalay , the capital of the Kingdom of Burma until 1885, had a flourishing amber industry. Mainly pearls, ear plugs and cigar tips were produced.

Probably the world's largest and most important collection of Birmit artifacts is in the American Museum of Natural History , New York. The collection also includes more than 3,000 arthropods . A large part of the museum's collection goes back to the private collection of Isaac Drummond, which the museum took over from his estate in 1933. The second-largest scientific inclusion collection of this amber with around 1,200 arthropods is located in the Natural History Museum in London.

Inclusions

♀ Earwig Astreptolabis ethirosomatia (Dermaptera) in Birmit. Holotype.

The only collection of organic inclusions established in Burma during the British Protectorate was acquired by the Natural History Museum in London in the 1920s . More recently, the New York Natural History Museum and some private individuals have created important collections. The age of the deposit was only recently determined from the fossils of this amber as Upper Cretaceous, after the Eocene age was assumed for a long time due to the fauna accompanying the formation from which the fossil resin is recovered. There are now more than 150 families of insects in Burmese amber, including the oldest known species of bees. Other organic inclusions in Burmese amber are bird feathers, remains of lizards , worms , snakes , colobus , scorpions , spiders , pseudoscorpions , mites , ticks , centipedes and millipedes . Twelve extensively examined pieces with well-preserved lizard remains provide an unusually deep insight into the Cretaceous, tropical lizard fauna. Also of interest are conical depressions in the fossil resin, which are interpreted as burial tunnels of mussels, which they created in the fossil resin after it was already stored in the water and hardened. Blood was found inside the body of a sandfly and a mosquito , and a microbe of the genus Leishmania known as a pathogen was found in the blood .

Botanical origin

Nuclear magnetic resonance spectroscopic (NMR) investigations on amber samples and analyzes of wood fibers enclosed in birmite indicate that the resin originated from a probably extinct member of the araucarias ( Araucariaceae ). It is possible that trees from the wing fruit family ( Dipterocarpaceae ) were also involved in the resin production.

Others

The Chinese word for amber is hu-p'o , which means something like tiger soul . This name goes back to an old popular belief that the soul of a dead tiger penetrates the earth and turns into amber. Nevertheless, the Chinese have known the true nature of amber since at least the fifth century AD. The Chinese scholar and alchemist Tao Hongjing wrote in the fifth century AD (translation from English d. V.):

“There is talk that the resin of the pine penetrates into the ground and is deformed into amber over millennia. If you light amber, a scent is created that is similar to that of pine resin. In some pieces of this amber, a single bee can be seen in the middle, which is no different in color or shape from a living bee. It must have been covered by the still liquid resin and so enclosed. "

The same author warned his compatriots against fake amber and referred to the electrostatic property of real amber to be able to attract straw to distinguish it from replicas .

From around 1910, counterfeits made of the newly developed plastic Bakelite increased . Since Bakelite has the same electrostatic properties as amber and is also very similar in color to the predominantly red birchite, replicas made from this material are difficult to identify.

literature

  • A. Ross, C. Mellish, P. York & P. ​​Tafforeau: Burmese Amber. In: Biodiversity of fossils in amber from the major world deposits. Ed .: D. Penney, Manchester (UK) 2010. ISBN 978-0-9558636-4-6
  • F. Noetling: On the occurrence of Burmite, a new fossil resin from Upper Burma. Records of the Geological Survey of India 26 (1), 1893, pp. 31-40.

Individual evidence

  1. ↑ a b A. Ross: Amber - The Natural Time Capsule. London 2009, ISBN 978-0-565-09258-0 .
  2. ^ RD Cruickshank & Ko Ko: Geology of an amber locality in the Hukawng Valley, Northern Myanmar. In: Journal of Asian Earth Sciences 21, Taipei 2003. pp. 441-455.
  3. ↑ a b c d O. Helm: Mittheilungen über Bernstein. XVI. About Birmit, a fossil resin occurring in Upper Burma. In: Writings of the Natural Research Society in Danzig , New Series, Volume 8, Volume 3 and 4, Danzig 1894, pp. 63–66.
  4. ↑ a b M. Kazubski: Burmite. Can it compete with succinite? In Bursztynisko 38, Gdansk 2016.
  5. ↑ HL Chhibber: Mineral Resources of Burma. London 1934; in Rice 1987
  6. ↑ P. Dahms: Mineralogical investigations on amber. In: Writings of the Natural Research Society in Danzig. New series, 8th volume, 3rd and 4th issue, Danzig 1894, pp. 97–114.
  7. ↑ a b c K. Andrée: The amber and its meaning in the natural sciences and humanities, arts and crafts, technology, industry and trade. Koenigsberg 1937
  8. ↑ B. Kosmowska-Ceranowicz: Amber deposits: geology, resources, modern extraction methods. In: Amber - Views - Opinions. Warsaw 2006, pp. 9-13.
  9. ↑ Resumption of funding (English) ( Memento of the original dated September 4, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.ambericawest.com
  10. ^ Poinar, Buckley & Brown: The secrets of Burmese amber. In: Mid-America Paleontology Society (MAPS) 20, Cedar Rapids (Iowa) 2005; Pp. 20-29.
  11. ↑ D. Quast, M. Erdrich: The Amber Road. Archeology in Germany, special issue 04/2014, Darmstadt 2013, ISSN 0176-8522.
  12. ^ A b c Petty C. Rice: Amber - The Golden Gem Of The Ages. 2nd Edition. New York 1987, ISBN 0-917007-20-5 .
  13. ↑ B. Kosmowska-Ceranowicz: New data on deposits of amber and other fossil resins . In: Amber - Views Opinions. Warsaw 2006, pp. 43–45.
  14. ↑ David A. Grimaldi: Amber - Window to the Past. New York 1996, ISBN 0-8109-1966-4 .
  15. ↑ Engel: New earwigs in mid-Cretaceous amber from Myanmar (Dermaptera, Neodermaptera) . In: ZooKeys 130, 2011: pp. 137–152. doi: 10.3897 / zookeys.130.1293
  16. ↑ Juan D. Daza, Edward L. Stanley, Philipp Wagner, Aaron M. Bauer, David A. Grimaldi : Mid-Cretaceous amber fossils illuminate the past diversity of tropical lizards. In: Science Advances , Volume 2, No. 3, March 4, 2016, e1501080, doi : 10.1126 / sciadv.1501080 Full text: pdf 1.3 MB
  17. ↑ Poinar, Lambert & Wu: Araucarian source of fossiliferous Burmese amber: spectroscopic and anatomical evidence. In: Journal of the Botanical Research Institute Texas 1, Fort Worth 2007, pp. 449-455.

Coordinates: 26 °  N , 97 °  E