There are exactly zero old growth redwoods left anywhere around SF Bay, including Muir Woods. There are a lot of pretty ones, but they're all second growth after total logging. You either have to go way north, or somewhat south on 1 to Big Basin etc near Santa Cruz. Some of the beaches do have massive gray waveworn redwood logs that are highly photogenic. If you look carefully, a number of beaches contain small pebbles of jade.