Spring 2022 G&G Available Now
May 13, 2022
A variety of topics are in store for you in the Spring issue of G&G. The first article provides a comprehensive summary of mineral, chemical, and spectroscopic investigations of Schneckenstein topaz. The second article concludes the investigation into the early mining history of the Habachtal emerald deposit in Austria with a look at the era between World Wars I and II. This issue also marks G&G’s return to the Tucson gem shows in early 2022 and the debut of an exciting new section: Diamond Reflections.
GEM TOPAZ FROM THE SCHNECKENSTEIN CRAIG, SAXONY, GERMANY: MINERALOGICAL CHARACTERIZATION AND LUMINESCENCE
The lead article by Manuela Zeug and coauthors provides a mineral-chemical and spectroscopic characterization of yellow topaz from the Schneckenstein crag in Saxony, Germany. This study utilizes excitation-emission spectroscopy to explain the photoluminescence behavior of the material, which appears virtually inert under common UV sources.
HISTORY OF EMERALD MINING IN THE HABACHTAL DEPOSIT OF AUSTRIA, PART II
Karl Schmetzer details the mining history of Austria’s Habachtal region to conclude this two-part series. This article presents research using largely unpublished materials from Austrian and German archives to illustrate the mining problems and the success or failure of those involved with emerald recovery in the era between World War I and World War II.
GIA laboratory staff members present their latest findings in the Lab Notes section, including a natural type Ia diamond that changed from Fancy Dark yellowish brown to Fancy Deep yellow-orange with HPHT processing, three green and yellow diamonds over 5 carats colored by nickel impurities, a record size for a CVD laboratory-grown diamond, and unusual laser drill holes in an HPHT-grown synthetic diamond.
The Micro-World section, dedicated to the inner world of gemstones, features an apatite before and after oiling, a large red garnet crystal within an aquamarine, magnificent cube-shaped cavities and purple fluorite in hyalite, and a complex fluid inclusion in topaz.
The debut of Evan Smith’s new G&G column explores the connection between deep-focus earthquakes, those originating below the rigid tectonic plates, and diamond growth. If these two processes are related, then modern-day earthquakes have the potential to produce valuable diamonds of large sizes. Future installments of this section will appear on a periodic basis.
GEM NEWS INTERNATIONAL
Finally, GNI correspondents from around the world report on market updates, interesting and noteworthy finds, and interviews with dealers, cutters, and designers, in more than 30 pages of coverage from the 2022 Tucson gem shows. Other highlights from the section include an unusual repair of a natural emerald, inclusions and spectroscopic features of yellowish green enstatite, and the discovery of davemaoite in a diamond from the earth’s lower mantle.
The Spring issue also contains the 2022 Gems & Gemology Challenge. Score 75% or better, and you’ll receive a certificate of completion; earn a perfect score, and your name will be listed in the Fall 2022 issue. Online entries for the Challenge must be submitted by Monday, August 1, 2022.
Brooke Goedert is editor of Gems & Gemology at GIA in Carlsbad, California.