Up at the very top of the public part of Mountain View Cemetery is this knocker. I think it has a mixture of rock types in it, but I haven’t lain down on it with my magnifier to tease them out. For now let’s call it greenstone, which is how the area is mapped. The stone is a bit dirty, unlike every other knocker in the yard. The groundskeepers ought to give it a good scrubbing with a water jet.
Across the road from here the other week, I passed a pile of rock and soil from a grave excavation and fingered a few of the stones—looked like a gray basalt. Greenstone is a mildly metamorphosed basalt; it often has wiggly veins of carbonate. See three examples starting here. It is somewhere between about 160 and 70 million years old, that is, Jurassic to Cretaceous.
The view of the bay and the city from up here is fantastic. The view of the hills has potential. The cemetery is slowly getting rid of the eucalyptus along the east side, and more and more of the lush hills and neighborhoods is visible every year.