Caribbean amber

Dominican Green Amber, natural without enhancement

Caribbean amber is amber from the island of Hispaniola, consisting of Haiti and the Dominican Republic; it is the only island in the Caribbean where amber retinite has been discovered and is mined. Dominican amber is found in various natural colors, among them fluorescent green and blue.[1] Dominican amber can be up to 40 million years old.[2][3]

Compared to copal

In recent years, some jewelry manufacturers have given the name "Caribbean Amber" to an industrially produced green gemstone made from hardened young tree resin, often copal from Colombia.[4] Colombian copal is sometimes only a few hundred years old and therefore relatively soft (Mohs 1 – 1.5).[5] But the desired appearance is that of old, transparent green Dominican amber.[6][7]

Autoclave process

A cylinder of Colombian Copal after the 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. The hardened copal lumps are made transparent by placing so-called water settlers (clarification needed) in the autoclave. The green color is 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.[8]

See also

References

  1. ↑ 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.
  2. ↑ Browne, Malcolm W. (1992-09-25). "40-Million-Year-Old Extinct Bee Yields Oldest Genetic Material". New York Times. Retrieved 2008-04-15.
  3. ↑ George Poinar, Jr. and Roberta Poinar, 1999. The Amber Forest: A Reconstruction of a Vanished World, (Princeton University Press) ISBN 0-691-02888-5
  4. ↑ "What is it and who makes it?". Amerheritage. 2009. Retrieved 2009-09-25.
  5. ↑ Platt, Garry (1997). "Properties of Amber". Garry Platt Amber Home. Archived from the original on 2009-09-17. Retrieved 2009-09-24.
  6. ↑ Gierlowska, Gabriela. "Amber Imitations -- Copal". Bursztynowy Portal. Retrieved 2009-09-24.
  7. ↑ Roskin, Gary (2006). "Caribbean Green Amber". JCK Online. Retrieved 2009-09-24.
  8. ↑ Roskin, Gary (2006). "Caribbean Green Amber". JCK Online. Retrieved 2009-09-24.
This article is issued from Wikipedia - version of the 11/15/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.