Her publicist provided no further details Thursday about the couple's breakup.
Lange and Twain, best known for her hits "Man! I Feel Like A Woman!" and "You're Still the One," recently opened a hiking trail on their property in New Zealand, fulfilling a pact designed to allay fears that wealthy foreigners were snapping up and sealing off the country's prime real estate.
Lange produced three of Twain's albums: 1995's "The Woman in Me," 1997's "Come on Over" and 2002's "Up!"