The Laguna Mountains are a small, weathered range of ancient metamorphic rock lying near the confluence of the Colorado and Gila rivers. The range is located right at the junction of the two rivers, about 6 miles northeast of Yuma. A mere 40 square miles in area, the Lagunas are essentially an outlier of the larger Gila range, lying just to the southeast. In fact, the two ranges are separated from each other only by the Gila River, which cuts through them on its way to the Colorado.
The Lagunas were once known as the San Pablo Mountains. The old Spaniards called them that. Just across the Colorado River from the Laguna Mountains a Spanish mission once stood. The mission was called San Pedro y San Pablo de Becuņer and was founded in 1780. It was only one of many missions established in the American Southwest by the early Spaniards.
Spanish presence in North America formally began in 1540 with Coronado's expedition. As with every officially-sanctioned expedition, the Spaniards brought along representatives of the clergy. Priests were an integral part of any Spanish conquest or colonizing effort. As it turned out, the various religious orders would have a profound effect on the history of the American Southwest. The mission system established by the religious orders provided a base from which the various Indian tribes could be converted and pacified.
The first missionaries in the land that would become Arizona were followers of St. Francis. They established at least 5 missions among the Hopi Indians during the late 1620's. In 1687, an event occurred that would firmly establish the Spanish mission system for the next hundred years. In that year, Father Eusebio Francisco Kino came to the northern Spanish province known as Pimeria Alta. This incredible man eventually founded 29 missions in Sonora, California, and Arizona before his death in 1711. In 1767, another famous priest came to the lower Colorado River country. Father Tomas Garces continued the good work of Eusebio Kino. Unfortunately, Father Garces was killed during the great Yuma Indian revolt of 1781. The missions were abandoned and the Spaniards were driven from the lower Colorado River basin. Ironically, only a year before, a new mission had been established just across the Colorado River from the Laguna Mountains (then known as the San Pablo Mountains). That mission was called San Pedro y San Pablo de Becuņer and it was surrounded by rich potholes of gold! These gold-bearing potholes occurred on both sides of the river. The deposits along the western flank of the Laguna Mountains were very rich. The potholes were worked by Spaniards, Mexicans, and American 49'ers on their way to the California goldfields. The gold occurs as placer deposits in gravel and in pockets, cracks, and potholes in the bedrock. A lot of gold still lies hidden in these natural pockets.
The history of mining in the lower Colorado River country of southwest Arizona formally begins with the 1582 expedition of Antonio de Espejo. Espejo came in search of three missing priests and a legendary lost lake of gold, but found silver instead in the Jerome area of central Arizona. In 1605, an expedition led by Juan de Onate and Marcos Farfan again penetrated the Arizona wilderness in search of mineral wealth. They conducted a fairly good reconnaissance of many of southern Arizona's mountain ranges. By the late 1700's, Spanish prospectors had combed most of the ranges in Arizona. They were followed by Mexicans in the early 1800's and then by the Americans in the 1850's.
When American prospectors entered the lower Colorado River country they found many old mines and prospect pits already in place. The Plumosa Mountains, Laguna Mountains, Castle Dome Mountains, and La Paz District in particular had abundant evidence of early Spanish and Mexican mining activities. Frequently, an American prospector would simply file a claim on any old mine or digging that he stumbled upon. The first real gold rush in Arizona occurred in 1858 and was precipitated by the discovery of rich placer gold near the Gila River, some 20 miles above its junction with the Colorado. The discovery was made by a member of the prospecting party led by Colonel Jacob Snively. The following years witnessed a number of major strikes in the mountains of southwest Arizona.
1862 was a pivotal year in the history of mining in Arizona. In that year, the rich goldfields of La Paz were discovered by an old mountain man and desert wanderer named Paulino Weaver. The huge lead and silver deposits of Castle Dome Peak were also discovered in 1862. The Castle Dome deposits were located by Jacob Snively, leader of the party that started it all back in 1858 at the Gila diggings. Snively is also given credit for the first discovery of silver in the Trigo Mountains, just north of the Lagunas.
The Gila Mountains slumber southeast of the Laguna range. The old Camino del Diablo (Devil's Highway) runs along the western flank of the Gila range. The "Devil's Highway" was used for many years by Spanish, Mexican, and American prospectors on their way to and from California. It is fascinating to think of just how close those early gold-seekers came to a truly fabulous lode as they passed by the Gilas.
The rich Fortuna vein was discovered in 1894. The gold-bearing vein was located on the west flank of the Gila Mountains, only a few hundred feet from the old Camino del Diablo trail! The Fortuna Mine produced nearly $3 million in gold before it was finally closed in 1904.
The placer deposits and potholes of the Laguna Mountains occur all along the western and southern margins of the range. Most of the richest deposits were near the river's edge, but gold has been found in cracks, crevices, and potholes in bedrock up to 100 feet above the river.