The debris is spread out on sheets of plastic on the cold dairy barn floor -- chunks of glass, vinyl records, broken plates and skeletons of an adding machine and typewriter.
Despite being dirty, charred and melted, the material is a collection of artifacts from the Burdell mansion at Olompali State Historic Park in northern Marin County, a prize that archaeologists say is a window into a colorful past.
"It may be one of the best collections of commune living, the sixties, the Summer of Love," said Marianne Hurley, a state architectural historian.
The artifacts are part of the asbestos-tainted debris from a fire that gutted the historic mansion Feb. 2, 1969, crashing a second-story bedroom into the downstairs kitchen and living area.
The materials, mixed with asbestos from the roofing and building insulation and too hazardous to handle, were stored in 24 55-gallon drums that were opened this week by workers in hazmat suits and then washed clean.
The mansion had been home to the Grateful Dead band in 1966 and to the Chosen Family commune from 1967 to 1969, when the residents were evicted after the fire and the tragic drowning of two children in the estate's pool.
"When you look at the hippie era, you look at it as recent history and it doesn't seem that important. But it's an important cultural period in the United States," said Victor Bjelajac, a state parks maintenance supervisor whose district encompasses Olompali.
The fire was only a chapter in the park's history, which stretches back 8,000 years to when the first Native Americans lived there, followed by Pomo and Miwok Indians who inhabited the site into the 20th century.
The Indian villages were visited by the Spanish, the Russians and possibly Sir Francis Drake, and had a role in the California Mission period. Olompali was the site of the only Bear Flag Revolt battle and then became a ranch and estate before being acquired by the state in 1978.
"It was a crossroads, everyone went there," said Breck Parkman, a state parks senior archaeologist. "If you were to only have one park to represent California, it would be a good one. History is inclusive at the park, including the hippie commune. We are all there in one way or another."