Polished Agate from the Lierbach Valley, Oppenau, Black Forest, Germany

Classic German Locality Specimen: Sawn and Polished Agate Nodule Half

This aesthetic small cabinet specimen is a classic example of German mineralogy: a characteristic sawn and highly polished half of an agate nodule from the Lierbach Valley near Oppenau in the Black Forest, Germany. The decorative collector’s specimen displays attractive concentric banding in warm earthy and natural tones, ranging from brown and orange to fine red and white lines.

Geological Record from the Rotliegend of the Black Forest

The renowned locality in the Black Forest is geologically associated with Permian quartz porphyry (rhyolite). Cavities formed by gas bubbles in the volcanic rock were gradually filled with agate and chalcedony deposited from silica-rich hydrothermal fluids over millions of years. Measuring 6.9 × 6.0 × 3.0 cm and weighing 146 g, this half agate nodule is an ideal size for display in a mineral cabinet. It is an excellent reference and documentation specimen that vividly records the fascinating volcanic history of southwestern Germany.