peperine

Century Dictionary and Cyclopedia

1. n. A volcanic tufa composed of well-developed crystals or crystal fragments cemented together. The name was first given to the tufas of the Alban Mount, near Rome. Tufa, tuff, peperine, pozzuolana, and trass are names given, without much discrimination, to deposits consisting essentially of more or less finely comminuted volcanic rock, cinders, and ashes.

Wiktionary

1. n. Alternative form of peperino.

GNU Webster's 1913

1. n. (Geol.) A volcanic rock, formed by the cementing together of sand, scoria, cinders, etc.