GIA (Thailand) - GIA Lab Bangkok,Special Report on Red Feldspar

Special report on red feldspar

GIA Laboratory, Bangkok

10th Floor U-Chu-Liang Building
968 Rama IV Road Silom Bangrak Bangkok
10500 Thailand

Tel: (66) 2 632 4090
Fax: (66) 2 632 4096
Email: info@giathai.net

Office Hours:
10.00 a.m. - 5.00 p.m. (Mon-Fri)

Gemology: Special Report on Red Feldspar:

This page contains a compilation of ongoing research into red feldspar and its sources around the world, as well as the detection of various color treatment processes.

The following reports were published in two parts:

August 01st, 2011 Release:

Andesine: Timeline of a Controversy
Richard W. Hughes

Geology and Field Studies of Reported Andesine Occurrences in the Shigatse Region of Tibet
Brendan M. Laurs, Ahmadjan Abduriyim, and Flavie Isatelle

Argon Isotope Studies of Andesine Collected During the 2010 Expedition to Tibet
George R. Rossman

Silver Incorporation in Inner Mongolian and Tibetan Andesine
Ren Lu, Emily V. Dubinsky, Troy R. Douthit, and John L. Emmett

Observations of Surface Residue Features Found on Andesine from China
Shane F. McClure

A Study of Andesine Matrix Specimens Purported to be from Tibet
Shane F. McClure, George R. Rossman, and Kenneth Scarratt

SEM Study of Red Andesine
Thanong Leelawatanasuk, Wilawan Atichat, Pornsawat Wathanakul and Namrawee Susawee

Separation of Natural Red Andesine from Tibet and Copper-Diffused Red Andesine from China
Ahmadjan Abduriyim and Ross Pogson

September 9th, 2009 Release

Introduction—Red Feldspar: A Puzzle to Fix

A Mine Trip to Tibet and Inner Mongolia: Gemological Study of Andesine Feldspar
Ahmadjan Abduriyim (Gemmological Association of All Japan-ZENHOKYO Laboratory)

The Red Feldspar Project
George R. Rossman (California Institute of Technology)

Copper Diffusion in Plagioclase
John L. Emmett and Troy R. Douthit (Crystal Chemistry, Brush Prairie, Washington)

Observations on Identification of Treated Feldspar
Shane F. McClure (GIA Laboratory, Carlsbad)

Observation on Effects of Heating and Copper Diffusion in Feldspar
Kamolwan Thirangoon (GIA Laboratory, Bangkok)

About gemological research at GIA:

For decades, GIA has been on the cutting edge of gemological research, analyzing data on gems and their characteristics. This effort becomes more challenging each year, as new gem sources emerge and new treatment processes and synthetic materials come onto the market. And if artificially enhanced gems and synthetics were left undetected, every gem and jewelry purchase would be a risk. GIA is dedicated to providing consumers the knowledge they need, and that’s why research is at the very core of GIA’s nonprofit mission.

Note: Comments on the reports and their direction are warmly welcomed as are offers of collaboration. Please contact: info@giathai.net stating the name of the project and name(s) of the author(s).