The silver mines of the Calico district have become famous for their yield of silver bullion. These mines are about six miles north of the Santa Fé railroad and near the station of Daggett. The belt extends in an easterly and westerly direction, and has been traced and developed for a distance of ten miles. The rocks of this region are violet or brown rhyolite, often porphyritic; green, yellow, and white tufa; greenish hornblende andesite; yellow and green breccia. Copper, lead, tin, zinc, iron, manganese, baryta, gypsum, sulphur, onyx, marble, asbestos, and gem stones are also found in the deserts. The minerals are scattered over the many thousands of square miles of territory. The difficulties of transportation, coupled with the lack of water, have greatly retarded the development of the known mineral fields, as well as prevented the finding of other rich deposits which doubtless exist. The character of the mineral rocks is multitudinous. In the Waterloo Mines in the Mojave Desert, ore is found in a belt of jasper which yields more than one thousand ounces of silver to the ton. Twenty-eight miles east of Daggett are large bodies of iron ore--the largest known on the Pacific Coast. These deposits have been practically undisturbed because of the distance from railroad and the lack of water and fuel to mine and smelt the ores. When a railroad is laid to the locality this field will prove a wonderful source of wealth to those who secure possession of it. Five miles south of Oro Grande are rich veins of copper which are found very near the surface. These deposits were discovered by the Mormons who settled on the Mojave River several years ago. Variegated marble quarries have been opened twelve miles northeast from Victor, in which are found marbles of wonderful beauty and fineness. Shades of crimson and gray, cream, rose, white, pale blue, black, chocolate, and yellow are mined from these quarries, the ledges of which outcrop and stand above the surrounding lands. Some of these marbles approach in beauty that of the finest onyx. The Colorado Desert contains numerous valuable gold mines, as well as silver, copper, tin, and other important minerals. Cement and asbestos are found in abundance in certain sections. Rich deposits of the latter mineral are found in the vicinity of Indio and at Palm Springs. Lithia rock and fine clay are mined in certain sections and in 1902 the richest known tourmaline deposits in America were found at Mesa Grande. There is an interesting story connected with the finding of these gems.