Caribbean amber

A cylinder of Colombian Copal after the autoclave process

"Caribbean Amber" is a commercial name for artificially treated Colombian copal.[1] There are no dates or specific geological information on Colombian copal. Because of its color and hardness, some scientists believe it may be Pliocene or Pleistocene, probably about 2 to 3 million years old, in some regions even up to 16 million years old, but in others much, much younger (Santander) and may only count with some thousands, or some hundreds of years. [2] Therefore, in its natural form it is relatively soft (Mohs 1 – 1.5).[3] But the desired appearance and behavior is that of the geologically older Dominican amber. The copal is modified by autoclave (see description below). Even though the process is similar to modifications or enhancements applied to some Baltic amber [4], it is sometimes considered considered an "amber imitation" due to its young age. [5][6]

Autoclave process

In the copal hardening process, the resin is wrapped in aluminum foil, then treated in the autoclave for several hours, increasing the temperature, pressure and heating time. Green or other colors are obtained by adding water at each stage of the process. After the copal has hardened, the aluminum foil is removed and the hardened resin is cut to produce the desired shape (i.e. bead or cabochon). It is then mixed with talcum and heated again in the autoclave. Thereafter, it can be cut and polished to obtain the desired finish.[7]

Amber from the Caribbean

Dominican Green Amber, natural without enhancement

Although there is also copal found in some parts of the Dominican Republic, (Cotui area), most of the Dominican retinite is the older Dominican Amber. The Dominican Republic is the only island in the Caribbean where amber has been discovered and is mined. Dominican amber is found in a range of colors, among them fluorescent green and blue.[8] Dominican amber was formerly thought to be up to 40 million years old,[9][10] however studies have narrowed the age down to approximately 16 million years old, dating to the Miocene Burdigalian.[11]

References

  1. ↑ "What is it and who makes it?". Amerheritage. 2009. Retrieved 2009-09-25.
  2. ↑ "Fossil Amber or Fossil Resin". FossilMuseum.net - Tree of Life - Fossil Amber. Retrieved 2017-06-02.
  3. ↑ Platt, Garry (1997). "Properties of Amber". Garry Platt Amber Home. Archived from the original on 2009-09-17. Retrieved 2009-09-24.
  4. ↑ Hoffeins, Christel (2012). "Baltic Amber - Autoclave Treatment". Polish Journal of Entomoloqy. Retrieved 2017-06-02.
  5. ↑ Gierlowska, Gabriela. "Amber Imitations -- Copal". Bursztynowy Portal. Retrieved 2009-09-24.
  6. ↑ Roskin, Gary (2006). "Caribbean Green Amber". JCK Online. Retrieved 2009-09-24.
  7. ↑ Roskin, Gary (2006). "Caribbean Green Amber". JCK Online. Retrieved 2009-09-24.
  8. ↑ L. Linati and D. Sacchi, V. Bellani, E. Giulotto (2005). "The origin of the blue fluorescence in Dominican amber". J. Appl. Phys. 97: 016101. doi:10.1063/1.1829395.
  9. ↑ Browne, Malcolm W. (1992-09-25). "40-Million-Year-Old Extinct Bee Yields Oldest Genetic Material". New York Times. Retrieved 2008-04-15.
  10. ↑ George Poinar, Jr. and Roberta Poinar, 1999. The Amber Forest: A Reconstruction of a Vanished World, (Princeton University Press) ISBN 0-691-02888-5
  11. ↑ Penny, D. (2010). "Chapter 2: Dominican Amber". In Penney, D. Biodiversity of Fossils in Amber from the Major World Deposits. Siri Scientific Press. pp. 167–191. ISBN 978-0-9558636-4-6.
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