About

Dr. Thomas Schröck

Founder and Chief Executive Officer

The founder and managing partner of THE NATURAL GEM has been active in international gemstone trading for 30 years. As a doctor of economics and a certified gemmologist in Switzerland, Germany and the USA, among other countries, he is one of Europe’s leading experts on naturally-coloured, untreated gemstones and investments in them.

His bestseller “Investing in Gemstones”, first published in 2017 and now in its third edition, is the first book to provide profound insights into the world of the most valuable stones in the world. It deals with both mineralogical and historical aspects of gemstones, explains what to look out for, and gives an overview of price developments.

Robert Ziegenfelder, MSc

Chief Operating Officer

Robert Ziegenfelder combines a solid career in emergency medical services with a commitment to teaching and strategic expertise, primarily through his academic training.

He brings a rare set of skills to the table, including extensive operational leadership experience in emergency and rescue management, teaching expertise in training and continuing education, and strategic knowledge gained through his academic studies. He combines efficiency and process thinking in emergency medical services with business acumen.