The ridge behind Woodminster Theater, in Joaquin Miller Park, is mapped as serpentinite. You start to notice this around the Moses pyramid, but as you explore you’ll find a lot more of it plus various associated metamorphic rocks.
For instance, on the Siwalik Loop Trail I spotted a fine chunk of actinolite schist, detailed below.
The ridge doesn’t have a name on the map, so I’ll give it one. It has the Moses pyramid, the Elizabeth Barrett Browning monument, the fireplace that Joaquin Miller built for his own cremation, and Lookout Point where Miller loved to contemplate Oakland and the bay. So by my decree, this is Visionary ridge.
At Lookout Point, the large boulders surrounding the viewing patio caught my eye. High-grade blocks!
A closer look showed me the garnet-muscovite-glaucophane association that marks blueschist. There was also some green (chromian) mica. Bring your magnifier, not your hammer, if you come this way.