Dominican amber
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2008-06-09T02:26:08Z
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[[Image:Ant in amber1.jpg|[[Ant]] in Dominican Amber|250px|thumb]]
'''Dominican amber''' is [[amber]] from the [[Dominican Republic]]. Resin from the extinct species ''[[Hymenaea protera]]'' is the source of Dominican amber and probably of most amber found in the tropics.
Dominican amber differentiates itself from [[Baltic amber]] by being nearly always transparent, and it has a higher number of [[fossil]] inclusions. This has enabled the detailed reconstruction of the ecosystem of a long-vanished tropical forest.<ref name=Poinar>George Poinar, Jr. and Roberta Poinar, 1999. ''The Amber Forest: A Reconstruction of a Vanished World'', (Princeton University Press) ISBN 0691028885</ref>
== Age ==
Recent studies reveal that it can be up to 40 million years old.<ref>{{cite web |url=http://query.nytimes.com/gst/fullpage.html?sec=health&res=9E0CE2DD123BF936A1575AC0A964958260 |title= 40-Million-Year-Old Extinct Bee Yields Oldest Genetic Material |accessdate=2008-04-15 |last=Browne|first=Malcolm W.|year=1992|work=New York Times|language=English}}</ref>
According to Poinar,<ref name=Poinar/> Dominican amber dates from [[Oligocene]] to [[Miocene]]. The oldest, and hardest of this [[amber]] comes from the mountain region north of [[Santiago de los Caballeros|Santiago]]. The ''La Cumbre'', ''La Toca'', ''Palo Quemado'', ''La Bucara'', and ''Los Cacaos'' mining sites in the ''Cordillera Septentrional'' not far from [[Santiago de los Caballeros|Santiago]]. <ref>{{cite web |url=http://ambarazul.com/wordpress/2006/09/ |title=Dominican Amber Mines: The Definitive List |accessdate=2008-04-15 |last=Corday|first=Alec|year=2006|work=The Blue Amber Blog|language=English}}</ref>There is also [[amber]] in the south-eastern ''Bayaguana''/''Sabana de la Mar'' area. There is also ''[[copal]]'' found with only an age of 15-17 million years.
== Mining Sites ==
There are three main sites in the [[Dominican Republic]] where amber is found: ''La Cordillera Septentrional'', in the north, and ''Bayaguana'' and ''Sabana de la Mar'', in the east. In the northern area, the amber-bearing unit is formed of [[clastic rocks]], washed down with [[sandstone]] and other sediments that accumulated in a [[River delta|deltaic]] environment, even in water of some depth.<ref>Leif Brost and Ake Dahlstrom. ''The Amber Book'', Geoscience Press, Inc., Tucson , AZ, 1996 ISBN 0-945005-23-7</ref><ref>Wilfred Wichard und Wolfgang Weitschat: ''Im Bernsteinwald''. - Gerstenberg Verlag, Hildesheim, 2004, ISBN 3-8067-2551-9</ref><ref>Baroni Urbani, C. & Saunders, J.B. (1980): ''The fauna of the Dominican Republic amber: the present status of knowledge''. – Memorias, 9a geologica del Caribe, 1: 213-223; Santo Domingo. (Published 1983).</ref>
In the eastern area, the amber is found in a sediment formation of organic-rich laminated sand, sandy clay, intercalated [[lignite]] as well as some [[Solvation|solvated]] beds of gravel and calcarenite.<ref>Schlee, D. (1984): ''Besonderheiten des Dominikanischen Bernsteins''. – Stuttgarter Beitr. Naturk., C, 18: 63-71; Stuttgart.</ref>
Both areas seem to have been part of the same sedimentary basin but were later disrupted by movements along major faults.<ref>Manuel A. Iturralde-Vennet 2001. ''Geology of the Amber-Bearing Deposits of the Greater Antilles''. Caribbean Journal of Science, Vol. 00, No. 0, 141-167, 2001</ref>[[Image:Leaf_in_dominican_amber.jpg|Leaf in Dominican Amber|left|thumb]]
== Mining ==
[[Image:ambermineinDR.jpg|thumb|right|Amber mine]]
[[Image:blue_amber_masbaha.jpg|thumb|left|A rare set of Arab worry beads ([[masbaha]]) made of Dominican [[blue amber]].]]Dominican Amber, and especially Dominican [[blue amber]] is mined through bell pitting, which is extremely dangerous. [[Bell pit]] is basically a foxhole dug with whatever tools are available. Machetes do the start, some shovels, picks and hammers may participate eventually. The pit itself goes as deep as possible or safe, sometimes vertical, sometimes horizontal, but never level. It snakes into hill sides, drops away, joins up with others, goes straight up and pops out elsewhere. 'Foxhole' applies indeed: rarely are the pits large enough to stand in, and then only at the entrance. Miners crawl around on their knees using short-handled picks, shovels and machetes.
There are little to no safety measures. A pillar or so may hold back the ceiling from time to time but only if the area has previously collapsed. Candles are the only source of light. Humidity inside the mines is at 100%. Since the holes are situated high on mountainsides and deep inside said mountains, the temperature is cool and bearable, but after several hours the air becomes stale. During rain the mines are forced to close. The holes fill up quickly with water, and there is little point in pumping it out again (although sometimes this is done) because the unsecured walls may crumble.<ref>Martínez, R. & Schlee, D. (1984): ''Die Dominikanischen Bernsteinminen der Nordkordillera, speziell auch aus der Sicht der Werkstaetten''. – Stuttgarter Beitr. Naturk., C, 18: 79-84; Stuttgart.</ref>
== Variations ==
'''Dominican amber''' can be found in many colors, besides the obvious amber. Yellow and honey colored are fairly common. There is also red and green in smaller quantities and the rare [[blue amber]] (fluorescent).<ref>Schlee, D. (1980): ''Bernstein-Raritaeten'' (Farben, Strukturen, Fossilen, Handwerk). – 88 S. (mit 55 Farbtafeln); Staatl. Museum fuer Naturkunde) Stuttgart.</ref><ref>{{cite web |url=http://dx.doi.org/10.1063/1.1829395 doi:10.10.1063/1.1829395 |title=The origin of the blue fluorescence in Dominican amber |accessdate=2008-04-15 |last=L. Linati and D. Sacchi|first=V. Bellani, E. Giulotto|year=2005|work=J. Appl. Phys. 97, 016101|language=English}}</ref>
The ''Museo del Ambar Dominicano'', in [[San Felipe de Puerto Plata|Puerto Plata]], well as the ''Amber World Museum'' in [[Santo Domingo]] have collections of amber specimens.
== References ==
<references/>
== External links ==
*[http://www.pbs.org/wgbh/nova/jewel/ PBS NOVA "Amber: Jewel of the Earth"]
*[http://www.smu.edu/isem/3D/3Dindex.html ISEM Research: Anolis lizard in amber]
*[http://www.amnh.org/exhibitions/amber/ American Museum of Natural History: Amber: Window to the Past, 1998]
*[http://www.emporia.edu/earthsci/amber/life.htm Life in Amber] includes numerous further links
*[http://palaeo.gly.bris.ac.uk/palaeofiles/lagerstatten/DomAmber/GeoAge.html Christine Lipkin, "Geological setting and age of the Domionican Republic"]
*[http://ambarazul.com/wordpress/2006/09/ Dominican Amber Mines: The Definitive List]
== See also ==
* [[List of minerals]]
* [[Ammolite]]
* [[Copal]]
* [[Blue amber]]
* [[Lagerstätte]]
[[Category:Fossil resins]]
[[Category:Miocene]]
[[Category:Natural history of the Dominican Republic]]
[[Category:Oligocene]]
[[Category:Paleontological sites]]