thumb|upright=1.2|Craigleith, an island in Scotland, composed of essexite
thumb|upright=1.2|Craigleith, an island in Scotland, composed of essexite
Essexite (), also called nepheline monzogabbro (), is a dark gray or black holocrystalline plutonic igneous rock. Its name is derived from the type locality in Essex County, Massachusetts, in the United States.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).