Sand Calcite from the Mályi Clay Pit, Hungary

This sand calcite specimen comes from the Mályi clay pit near Miskolc in Borsod-Abaúj-Zemplén County, Hungary. Numerous rounded to nodular aggregates are intergrown into a three-dimensional, branching group.

The individual aggregates show spherical to bubble-like forms and in places resemble a chain or a grape-like cluster. Their surfaces are matte and have a sandy texture. The color ranges from sandy white through cream to beige.

Measuring 8.5 × 6.5 × 5.0 cm, the piece belongs to the cabinet specimen size category.

Formation of Sand Calcite from Mályi

The Mályi clay pit exposes Pannonian clay, silt, and sand sediments. Characteristic intergrown sand calcite nodules and rounded aggregates are known from the locality.

The aggregates formed within unconsolidated sediments through the precipitation of calcite from mineral-bearing pore waters. During growth, numerous sand grains were incorporated into the calcite. The calcite acted as a mineral cement, consolidating the surrounding sediment into the rounded forms visible today.

The unusual three-dimensional habit, matte sandy surface, and documented provenance make this piece a characteristic sand calcite specimen from Mályi.