Herausgeber: Deutsche Gemmologische Gesellschaft e.V. Prof.-Schlossmacher-Str. 1 D-55743 Idar-Oberstein
Copyright: Für alle Beiträge behält sich die Deutsche Gemmologische Gesellschaft (Deutsche Gesellschaft für Edelsteinkunde) e.V. sämtliche Rechte vor, insbesondere die des Nachdrucks, der Übersetzung in andere Sprachen und der photomechanischen Wiedergabe. Die veröffentlichten Beiträge stellen – soweit namentlich bezeichnet – die Auffassung der Autoren dar und geben nicht notwendig die Meinung von Herausgeber und Schriftleitung wieder. (Content of this journal may not be reproduced in any form without the permission of the German Gemmological Association. Opinions expressed do not necessarily reflect the views of the Association.)
In addition to the red and orange garnets described in previous blog articles, the green minerals or varieties of this extensive mineral group are particularly important in the...
The classic garnet is the red garnet, which has been used for jewellery purposes since ancient times ( more information… ). However, during the 20 th century, several gemstones...
This year, the German Gemmological Association (DGemG) is celebrating the 50 th anniversary of its training centre in Idar-Oberstein. The first gemmological seminars were held...
Ladies and gentlemen, It is a pleasure to be with you all here in Idar-Oberstein, a beautiful town that I have visited often and to which I am always pleased to return – not...
Dear State Secretary Petra Dick-Walther, Dear Lord Mayor Frank Frühauf, Dear President of the World Jewellery Confederation CIBJO, Dr. Gaetano Cavalieri, Distinguished speakers...
The current issue of Gemmologie - Zeitschrift der Deutschen Gemmologischen Gesellschaft e.V. is available to members in the online archive The magazine is also available as a...
The speakers at the two-day anniversary conference '50 Years of DGemG Training Centre': Dr. Claudio Milisenda, DSEF Idar-Oberstein, Germany, Qi Wang, DGemG Idar-Oberstein,...
SAVE THE DATE This year we celebrate the 50th anniversary of our full-time training centre for gemmology. Already since the first years after the German Gemmological Association...
The classic colour of garnets is red. The oldest finds of garnet jewellery as grave goods date back to the Bronze Age over 5000 years ago. Garnet jewellery flourished in...
The field of Gemmology with its gemmological examination methods is constantly evolving. Classical methods such as investigation with polariscope, refractometer and microscope...
Tanzanite is often called the "stone of the 20th century", as it was discovered in 1967 and became the first popular natural "substitute" for the blue colour of sapphire. Gübelin...
The name spinel can be traced back to the 16th century. It was mentioned for the first time in 1533 by C. Leonardi, and Georg Agricola (1494-1555) wrote in "De Natura Fossilium":...
Recently, the authors examined a 17.20 et greenish blue oval cabochon that exhibited a noticeably blurry, uneven colour distribution (Figure 18). lt had a spot RI of 1.57, as...
Fig. 1: Yellow sapphire of 4.57 ct with a unstable colour. (A) shows the stone as it was submitted for examination, (B) after a fading test under a strong lamp for 15 min, (C)...
Emeralds from various deposits in Pakistan (Chitral, Swat and Khaltaro) and Afghanistan (Panjshir and Laghman) were examined and compared. In addition, we compared the...
Occurrences of opal in the Central American country Honduras are already known since the mid-19th century. Opals with and without playof-colour are found in volcanic rocks,...
The use of emeralds for jewellery dates to Egyptian times, when greenish crystals found in the Gebel Sikait area were known as early as 3500 BC. The pits in the area later became...
Padparadscha is undoubtedly one of the rarest gemstones. The corundum variety, whose most important deposits are the gemstone placers of the island of Sri Lanka (Ceylon),...
Purple-pink coloured garnets with blue apatite inclusions have been on the market for some time and are becoming increasingly popular. The garnets come from a location in...
One of the most important reasons for the almost simultaneous founding of the first gemmological associations in the 1930s (Gemmological Association of Great Britain and...
Unlike other industry sectors which come to a standstill as local rough material production becomes scarce, the gemstone industry in Idar-Oberstein endures, 150 years after the...
One of the most well known and popular natural glasses is moldavite, which formed during a meteorite impact about 14.8 million years ago. Today, moldavite is mainly obtained from...
As long as people have adorned themselves with gemstones, they have also tried to enhance the beauty of these natural products. Treatment options have been used for centuries to...
Gem-quality blue gahnite from Jemaa in central Nigeria has gemmological properties (RI and SG) and a chemical composition indicating relatively pure gahnite (90.7–91.3%). The...
On the 13th of January 2024, the "Escola de Gemmologica" of the Faculty of Earth Sciences at the University of Barcelona hosted the 24th symposium of the "Federation for European...
You want to extend your knowledge in gemmology? You are looking for practical and feasible ways to add advanced methods to your gemmological laboratory? Due to the steady...
