Showing posts with label copper diffusion. Show all posts
Showing posts with label copper diffusion. Show all posts
Tuesday, May 19, 2009
Grain Boundary Diffusion in Tourmaline; The Epochal Crisis, Part II; A Tempest in a Tabloid:
An Open Letter to David Federman, Editor-in-chief, Colored Stone.By Richard W. Wise, G.G.©2009David Federman, I just finished reading Joel Arem’s article Ending Diffusion Confusion in the current issue of Colored Stone together with your editorial titled Some Badly Needed Science. You have written so many open letters to the gemstone industry I thought I would try my hand at writing one to you.
Wednesday, October 22, 2008
Copper Diffusion: Is It Gemology's New Worst Nightmare? Part II
An exceptional emerald crystal:This month’s feature on the R. W. Wise website is an exceptional Colombian emerald crystal. It was found at the La Pita Mine, part of a complex of mines of the same name that I visited during my last buying trip to Colombia.Historically gems of this quality were found at the old mines like Muzo and El Chivor. Chivor was appropriated by Spanish conquistadors in 1550;