Coney Grade Site, Santa Monica Mts., Ventura Co., California
The dark colored basalt of this specimen is filled with small vesicles filled with white Mordenite. There is a large area on one surface covered with Mordenite composed of tangled and matted fibrous crystals. There is also present an unidentified black material. From a very obscure location.
The specimen is in good condition with no appreciable damage.