steep slope of volcanic rhyolite tuff rubble just below cliffs at upper canyon rim. This site has been destroyed by a new paved highway to Batopilas that also limits easy access to many former rich roadside collecting sites in the canyon.
on steep slope of exposed outcrop of volcanic rhyolite tuff below cliffs at upper canyon rim. This old switchback road has now been replaced with a new paved highway to Batopilas that greatly limits access to many former rich roadside collecting sites in the canyon.
