From the moment he first took up the stones, Bruce Baltz fell into a natural rhythm, quickly learning how to use them in a massage. Eventually the stones would bring about profound changes, leading him to a spirituality that had been missing in his life.

Others, such as Melissa Hurt, who works as a makeup artist in Washington, D.C., found that the physical changes that took place during the massage were "phenomenal." During the hour and a half she spent on the massage table, Hurt experienced "a ballet of colors" in her mind.

No one it seems is lukewarm about LaStone Therapy, a new kind of massage that uses smooth hot and cold stones to relax muscles and release tension. LaStone is sweeping spas throughout the United States and overseas, where everyone is singing its praises and some are exploring its spiritual side.

Thermotherapy - the application of heat - relieves sore muscles, helping to alleviate the stiffness brought on by too many hours at a desk and the stress of everyday life. LaStone therapy, which has its origins in Native American culture, can be a spiritual experience for those seeking a connection linking body, mind and soul in their daily lives, according to company literature.

Its creator, Mary Hannigan, says that the idea for LaStone first came to her on Aug. 19, 1993, when a voice said to her: "Use the stones." At the time, she was sitting in a sauna with her niece. The voice became so insistent that Hannigan finally picked up two stones and massaged her niece's back with them.

That moment launched an industry based in Hannigan's hometown of Tucson, Ariz., and a movement that its followers say draws energy and spiritual strength from the stones.

For Hannigan, the stones are a link to Mother Earth. Contact with the stones connects an adult with nature, reminding him or her of what it was like as a child to roll down a hill and lay in cool grass on a hot summer day, "For others the spiritual connection can be on much deeper levels, taking you to places deep within your being for healing emotional distress and anger," she says.