The peppermint herb Mentha piperita, when grown in different regions and soils, can yield essential oils with varying composition and organoleptic profiles. Some of these oils with specific flavor profiles command a premium value whe traded commercially.
Peppermint is a widespread herb, as demonstrated in Lawrence's reviews on its origins and essential oil composition. These excellent reviews are the starting point for this study.
Cornmint, or Mentha arvensis, is known confusingly in parts of Europe as peppermint. The chemistry of Brazilian, Chinese and Indian M. arvensis oils from several years' crops was reported in an excellent review by Boelens.