Stapel van Stenen Newsletter

Rolf Egberink’s Stapel van Stenen Newsletter for July-August is out.

• Sainte-Marie-aux-Mines 2026 Report: Rolf attended the largest European mineral fair in late June, despite extreme heat (+35°C). He focused on feldspars, new discoveries, and trends like “Golden Quartz” (quartz coated with a thin gold layer via sputtering). He noted recurring materials such as Chinese fluorite on quartz, Moroccan “citrine” (misnamed; colour linked to bituminous inclusions), and synthetic quartz. The fair inspired future articles, videos, and courses.

• Guest Article: New Finds from Qinglong, China: Ed Richard (Pristine Minerals) contributed a guest article on Qinglong, Guizhou, highlighting exceptional fluorites and new mineral species (possibly two undiscovered ones). The article is available in Dutch and English.

• Fluorescent Amethyst from Brazil: Investigated UV-reactive yellow phantoms in amethyst from Bahia, Brazil, often marketed as “Powellite Quartz”. Conclusion: While early analyses suggested powellite, newer studies point to organic fluorescent compounds as the likely cause. The debate underscores the importance of distinguishing between hypotheses and confirmed research.

• Museum Visits: Leipzig and Freiberg:

  • Beucha Porphyry: Recognised this distinctive rock (with large feldspar crystals and xenoliths) in Leipzig’s Völkerschlachtdenkmal, previously seen in Enschede’s town hall.

  • Terra Mineralia (Freiberg): One of Europe’s most impressive mineral collections, housed in Freudenstein Castle, with stunning displays and photography-friendly showcases.

  • Krüger-Haus (Freiberg): Focuses on German minerals, particularly Saxony’s mining history. Complements Terra Mineralia’s global scope.

Upcoming Activities

• August 23: Family Day at Maastricht Natural History Museum (free mineral identification).

• August 30: South Limburg International Mineral Fair (Vaeshartelt Castle, Maastricht).

• September–October: Lectures, fairs (e.g., Rijswijk, Haarlem, Munich), and live Q&A sessions for the Basic Mineral Recognition Course and Sellers Community.

Below: A collage of the many top pieces of rhodochrosite from one mine in South Africa that are on display in Terra Mineralia.