Hematite QuarryHematite, the mineral form of iron oxide, was highly prized by the Ohlone and Miwok triblets surrounding San Francisco Bay. It was the principal source of red ochre, used in burials, ceremonies, and pigments. Hematite outcroppings near the intersection of Redwood Road and Mountain Boulevard in Oakland undoubtedly supplied much of the prehistoric Bay […]
Mallory Creek Village.45 bedrock mortars in a small village on a shelf above Mallory Creek.18 cupules at one bedrock mortar station.Elevation 655 ft.This is a beautiful site in a secluded glade.Look for the old Indian trail leading to sites further up Mallory Creek.Bob stands in a possible housepit.How much dirt has washed down on this […]
Bob’s Mortar75 bedrock mortars, including 9 in a satelilte site about 100 ft. awayElevation 1380 ft.This site was named for the first mortar Bob discovered on his own. It is a single large bowl on a rock right beside the trail. Below the rock a small perennial spring or seep dribbles water into a creek […]
Keller RanchTwo portable stone mortars incorporated into the ranch house foundation, which was constructed on an extensive midden deposit.Elevation 393 ft.A major Chupcan village occupied this area at the confluence of Donner, Mitchell, and Diablo Creeks.One of the portable mortars in the ranch house foundation.Obsidian debitage picked up from the ground surface around the ranch […]
Upper East Morgan Territory RidgeSix bedrock mortars.Elevation 1952 ft.There are two clusters of mortar rocks at this site. The second cluster lies about 250 ft. to the northwest.There are great views of the Central Valley from this shelf, and it’s only 35 minutes from the Morgan Territory parking lot. A great place for a picnic.
Lower Mallory Creek2 bedrock mortars and 1 possible mortarElevation 533 ft.Thank you Master Site Finder.Bob straddles the upper mortar of a pair. It’s a comfortable working position.A closer look at the mortars. Both are small cones with hi/lo rims.Be sure to continue up the creek until you reach a group of mortars on a bedrock […]
Riggs Canyon Rock Camp113 bedrock mortars in a beautiful picnic site.Elevation 1306 ft.The Riggs Canyon Rock is a wonder. It is covered with more than 40 mortars, many of them ground into the base of geoconcretions. (In a geoconcretion a harder rock embedded in a softer rock is extruded over time due to various forces. […]