The Tucson and Amole Mountains are so accessible for visitors to Tucson that it is believed a brief description of the geology and mineral resources of these mountains will prove welcome. It is perhaps unfortunate that the purpose for which the data incorporated in this report were gathered made it unnecessary or undesirable to go more fully into details; but the general public may find this brief report more interesting and useful than one more voluminous and comprehensive. The complexity of their geology, the variety of their igneous rocks, and the diversity of their ore deposits all combine to make the Tucson and Amole Mountains a very rich field for students and scientists. The general public, also, find these mountains interesting because of their picturesqueness, the heavy growth of sahuaro cactus existing in portions thereof, and the Indian pictographs and other evidences of a past civilization found at several points therein. In addition, a number of petrified trees of large size have been found near the Ajo road on the west side of the Amole Mountains, and this feature is destined to attract increasing attention. 25 p.