Natrolite from the Richter Quarry near Hammerunterwiesenthal, Germany

This natrolite specimen comes from the Richter Quarry near Hammerunterwiesenthal in the Saxon Ore Mountains. Numerous white to cream-colored natrolite crystals cover a large area of the dark phonolite matrix.

The elongated crystals are densely intergrown and form partly radial groups. Some crystals project freely from the more compact aggregates. Their surfaces appear matte to silky.

Measuring 7.0 × 5.5 × 4.0 cm, the piece belongs to the cabinet specimen size category. It weighs 128 g.

Natrolite from a Phonolite Occurrence in the Ore Mountains (Erzgebirge)

The Richter Quarry near Hammerunterwiesenthal is a well-known German locality for natrolite and other zeolite minerals. The quarry exposes phonolite in which various secondary minerals formed in fractures and cavities.

Mineral-bearing fluids circulated through open spaces within the volcanic rock. Natrolite was deposited on the cavity walls and formed dense, partly radial crystal aggregates.

The pale crystal groups, dark phonolite matrix, and documented provenance make this piece a characteristic natrolite specimen from Hammerunterwiesenthal.