The unique properties of pumice are the result of its origin as volcanic lava that underwent the simultaneous actions of rapid cooling and rapid depressurization. The rapid cooling and depressurization that pumice underwent resulted in a network of porous voids within the glass structure, similar to a sponge. This is the reason for the light weight and mildly abrasive nature of pumice that accounts for many of its industrial applications. While pumice is an igneous rock, it is actually a kind of non-crystalline glass and not a mixture of minerals.
Since pumice is the result of volcanic activity, it is not readily found in commercial quality and quantity. Individual pumice deposits, while similar in basic properties, are all unique.
The CR Minerals pumice deposit west of Espanola, New Mexico is unique in its consistent balance of light weight, porosity, abrasiveness, color, and chemistry. It is the result of the eruption that created the Valles Caldera, some twenty miles from our mine site, more than 1 million years ago. The combination of unique properties makes CR Minerals pumice suitable for most pumice applications, and its light weight and purity sets it apart from other pumice produced in North America.
