Serpentine is the state rock of California. California was the first state to select a state rock. (1) In San Jose, serpentinite (which is technically the name of the rock while serpentine is the name of the group of minerals that make it up) is plentiful. A great place to see lots of it is in Santa Teresa County Park in south San José.
“In 1965, the California legislature chose serpentinite as the official state rock. …No one knew serpentinite, so emblematic of California, isn’t native to the state. Arguably, no rock is native to California since virtually the entire state is built of imported geology. …Wherever you stand in this state, if your feet are on bedrock, the odds are that you are standing on an immigrant, reeled in by subduction from the far reaches of the Pacific in the process of assembling California.” – Dr. Keith Meldahl, professor of geology and oceanography. (2)
1. https://statesymbolsusa.org/symbol-official-item/california/state-rock-mineral/serpentine , 2020.
2. Rough-Hewn Land, book by Keith Meldahl, 2011, page 18.