Natrolite from Hammerunterwiesenthal, Germany

Natrolite from Hammerunterwiesenthal in the Ore Mountains has been well known among regional and systematic mineral collectors for many years. Particularly characteristic are the white to cream-colored, needle-like crystals on gray phonolite matrix.

Hammerunterwiesenthal in the Saxon Ore Mountains

Hammerunterwiesenthal is a district of the town of Oberwiesenthal in Saxony’s Erzgebirgskreis. The village lies on the ridge of the Central Ore Mountains at an elevation of about 810 meters, only a few kilometers from the border with the Czech Republic.

Mining has a long tradition in the Ore Mountains. Directly near Hammerunterwiesenthal lies the so-called Richterbruch, a former phonolite quarry. Quarrying began there as early as 1897 and ceased in 2015. Today, the quarry is largely abandoned and is increasingly being backfilled. As a classic mineral locality, it is now considered largely exhausted.

Minerals from the Richterbruch Quarry near Hammerunterwiesenthal

The Ore Mountains are known for an extraordinary diversity of minerals. Classic ore minerals and silver discoveries in particular have made the region internationally famous.

Hammerunterwiesenthal, however, is especially known for minerals of the zeolite group. Natrolite is the most common, frequently intergrown with thomsonite. Analcime was also not uncommon at this locality. Other minerals found there include chabazite, gonnardite, phillipsite, and calcite.

Natrolite from the Ore Mountains

The phonolite of Hammerunterwiesenthal is a Tertiary volcanic rock. Particularly sought after were natrolite specimens from cavities and vugs within the phonolite.

Natrolite typically forms snow-white to cream-colored, needle-like crystals with a silky luster. The crystals may form radial-fibrous aggregates or dense crystal coatings on the matrix. They frequently occur together with other zeolites.

Particularly attractive is the strong contrast between the light-colored natrolite crystals and the gray phonolite matrix. This combination makes the specimens interesting to both regional collectors and systematic mineral collectors.

Natrolite from Hammerunterwiesenthal – Also Available in the Shop

Selected natrolite specimens from Hammerunterwiesenthal and other localities are also available in my Natrolite category. There, different crystal forms and localities can be compared directly.