jaspilite

Century Dictionary and Cyclopedia

1. n. In petrography, originally an acid igneous rock more silicious than rhyolite; as now used, in the Lake Superior region, a rock consisting of bands of red chert and hematite.

Wiktionary

1. n. mineralogy A compact siliceous rock resembling jasper.

GNU Webster's 1913

1. n. (Min.) A compact siliceous rock resembling jasper.