Uraninite (Czech)

A genuine uraninite specimen from the Czech Republic featuring abundant dark uranium-bearing mineralisation hosted within a contrasting pink to cream-coloured crystalline matrix rich in quartz and feldspar-like gangue minerals. The specimen displays numerous scattered uraninite crystals, rounded masses, and black uranium-rich patches distributed across the surface, creating excellent visual contrast and showcasing the complex geological environment in which this historic uranium ore formed.

Under magnification, the specimen reveals a fascinating mineral assemblage consisting of lustrous black uraninite crystals, botryoidal uranium mineralisation, translucent quartz-rich material, and pale cream secondary mineral coatings. Several areas exhibit well-defined uraninite crystal faces and rounded uranium-rich structures embedded throughout the host rock, producing an attractive texture highly sought after by collectors of radioactive minerals and classic European uranium specimens.

Microscopic examination reveals a remarkable range of mineralogical textures, including glossy black uraninite crystals, concentric growth structures, crystalline fractures, and delicate alteration features associated with natural uranium weathering processes. Small yellow-green areas of secondary uranium mineralisation are visible within portions of the specimen, highlighting the ongoing transformation of primary uranium minerals through geological time.

The specimen also contains delicate fibrous mineral growths visible under magnification within isolated areas of the matrix. These fine white fibres may represent an asbestiform mineral habit occasionally encountered within hydrothermal uranium-bearing vein systems. While only present in very minor amounts, these naturally occurring fibrous features contribute additional geological interest to the specimen. As with all mineral specimens containing unidentified fibrous minerals, handling should be minimised and the specimen should remain within its display box whenever possible.

Under ultraviolet light, portions of the specimen exhibit scattered bright green fluorescence associated with secondary uranium minerals formed through the natural alteration of uraninite. These fluorescent zones create striking contrast against both the dark uranium-rich mineralisation and the pale crystalline host rock, enhancing the specimen's display appeal and demonstrating the complex mineralogical evolution of the deposit.

The combination of abundant uraninite mineralisation, contrasting crystalline matrix, fluorescent secondary uranium minerals, microscopic crystal development, and intriguing geological textures makes this an attractive collector specimen from one of Europe's most historically important uranium-producing regions.

The specimen measures approximately 60 × 35 × 20 mm, weighs approximately 67.3 grams, and is supplied in a protective acrylic display box, ready for display, storage, or collection.

Specifications

Equipment Used To Measure: RADEYE B20-ER

Activity Including (Alpha, Beta & Gamma): 160,000 cpm

Mineral: Uraninite (Pitchblende)

Formation: Uraninite with Secondary Uranium Mineralisation

Origin: Czech Republic

Weight: Approx. 67.3g

Size: Approx. 60 × 35 × 20 mm

Display: Includes Acrylic Display Box

Features: Natural Uraninite Mineralisation • Quartz-Rich Crystalline Matrix • Green Fluorescent Secondary Uranium Minerals • Well-Defined Uraninite Crystals • White Secondary Mineral Coatings • Minor Fibrous Mineral Growths • Historic Uranium Mining District Specimen

Collector Specimen ☢️

Each specimen is completely natural and unique, preserving mineralogical features formed over millions of years within one of Europe's most famous uranium-producing regions. This specimen offers an excellent combination of visible uraninite crystal development, attractive crystalline gangue minerals, fluorescent secondary uranium mineralisation, and fascinating microscopic textures. A remarkable example of natural uranium mineralisation and an outstanding addition to any radioactive mineral, uranium ore, fluorescent mineral, or geological collection.