SAN FRANCISCO, Aug. 11 – San Francisco society circles still were in shock today over the death of Abigail Folger, the pretty heiress slain in a mysterious weekend massacre at Bel Air.

Miss Folger, 26, was the daughter of Peter Folger of Woodside, chairman of the J. A. Folger & Co. coffee firm. Friends described her as a restless young woman interested in liberal causes.

She was an honor student at Radcliffe and had worked in a New York bookstore and an art museum at the University of California at Berkeley before becoming a social worker and going to the southern California area.

She worked for some time in the ghetto area of Watts and also labored in Thomas Bradley’s losing in mayoralty campaign a few months ago.

With her family’s approval, she invested money in the chain of salons operated by male hair stylist Jay Sebring, 35, also killed in the weekend slaughter. Other backers included actors Paul Newman, Steve McQueen, Warren Beatty and Peter Lawford.

Through Sebring, she met and mingled with many of Hollywood’s most famous names.

But she had the misfortune to be at the wrong place at the wrong time last weekend.

Sebring was also well known in the Bay Area where he opened a hair styling salon last May in partnership with public relations executive Art Blum.

Blum, who said he was in a state of “stupor” from the tragedy, denied reports characterizing the five persons slain as “rich hippies.”

Blum said Sebring was “not even much of a swinger. His ambition was to become a millionaire.”

When Sebring came to the Bay Area, he would usually visit Lt. Col. Paul J. Tate.

Tate, father of slain actress Sharon Tate, 27, is nearing retirement as assistant chief of staff for intelligence at the Sixth Region Army Air Defense Command at Fort Baker here.