High Quality Content by WIKIPEDIA articles! The Permanente Quarry is a limestone quarry in Cupertino, California. The quarry is a limestone and aggregate mining operation and cement plant, owned by Lehigh Southwest Cement, a subsidiary of HeidelbergCement. Located in the foothills above Cupertino on the northeast slopes of Black Mountain, the quarry runs east-west parallel to the upper watershed of Permanente Creek to the south and to Permanente Ridge and Rancho San Antonio Open Space Preserve to the north.