"It was totally engulfed in flames," one man told ABC7.
The fire broke out around 9:30 Wednesday morning and the house was quickly surrounded by flames. Crews from five different departments raced to the hillside home along Lynford Drive.
"Within several minutes, it had gone to a first alarm, second alarm... Several minutes later, gone to a third and fourth alarm," said Jessica Power with the Tiburon Fire Department .
Residents in the exclusive community watched as the 3,800-square foot house burned, fearing the fire might spread to their homes next.
"I couldn't figure out which neighbor it was that was on fire. It just looked like it could have been the whole area up there," said neighbor Carolyn Friedman.
"A new house just sold down here for a little under six million. This house just got rebuilt, sold couple of years ago for five, four... and they put almost two million in it, completely remodeled it," said another neighbor Jordan Rogers.
The fire was put out before it could spread thanks in large part to two recent rain storms which helped dampen a lot of the trees nearby. Still, the home belonging to one of the city's most-beloved residents is a total loss.
Barbara Meislin is better known as "The Purple Lady."
"She's the most fabulous person on the planet. She loves everybody, and cares for everybody, and wears purple because it's a very healing, loving color," said Friedman.
"The Purple Lady," as she is known, is in her 70's and has lived in Tiburon for more than 40 years. She is staying with neighbors while she finds a new home.
Investigators are looking at a downstairs furnace as one possible cause of the fire.