Readers in the UK will recognize this song from British Air commercials. Other readers will recognize it from Ghiradelli commercials, or Godiva commercials. It's quite famous, and most of you have all heard this before.
It's a striking piece - opera doesn't have many duets between sopranos. It's from the opera Lakmé and is from the scene where Lakmé (daughter of a Brahmin) and her servant Mallika gather flowers by the river. Thus the name.