There are at least four bands called GEM (or Gem):
1. GEM is a rock band from Utrecht, The Netherlands.
2. Gem is a 1990s band from Ohio with members from Guided By Voices, Doug Gillard and Tim Tobias.
3. ＧＥＭ (Girls Entertainment Mixture) are a Japanese idol group and are the 3rd group to stem from iDOL Street. Sister group of SUPER☆GiRLS and Cheeky Parade.(PLEASE! CORRECT TAG TO ＧＥＭ )
4. GEM was a short lived female trio consisting of former Spice Girls Geri, Emma and Mel B.