Davie Tennis Stadium is a set of courts in a former quarry, administered by Oakland but situated within Piedmont. But what about the stone, you ask.
I haven’t checked the whole place out, but the exposures near the entrance display this dark chert or siliceous metashale. The quarry exploited the Novato Quarry terrane of the Franciscan complex, a large pod of which underlies Piedmont and its immediate surroundings. The terrane is mostly sandstone, but some fine-grained rocks occur in it too.
I’ll be leading a walk to this and three other Oakland quarries for the Oakland Urban Paths organization on February 11. Watch the OUP site for details.