Emerald vs Greenstone

Emerald

name

  • The Rural Municipality of Emerald No. 277, a rural municipality in eastern Saskatchewan, Canada. 

  • A town in Queensland, Australia. 

  • A female given name from English. 

Greenstone

name

  • A municipality in Thunder Bay District, Ontario, Canada. 

  • A surname. 

How often have the words Emerald and Greenstone occurred in a corpus of books? (source: Google Ngram Viewer )