Clemens & Stephan Schwarzinger Talk for Tucson Gem & Fine Mineral Show 2026

Stephan and Clemens Schwarzinger both hold PhDs in Chemistry and work as professors at the Universities of Bayreuth, Germany and Linz, Austria. They were introduced to mineral collecting in their childhood through their father and remain deeply involved in the field today. While Stephan specializes in fraud detection within the food industry, Clemens focuses on scientific gemology and works as a gem cutter.

In their presentation, they will give an overview of what’s happening in the mineral market regarding fakes, mounted specimens, and treatments – and how such issues can be detected. In addition to simple tests and practical advice on what to look for before buying, they will also discuss various scientific testing methods that can reveal treatments and, in some cases, help determine a specimen’s origin.