Many mule loads of silver taken at various times from large shipments, likely headed south from New Mexico to make their way to Spain. A rich gold vein high on the mountain is also mentioned. New Mexico has some major Silver mines nearby like the Bridal Chamber at lake Valley, Kingston, Silver City, Hermanas, and so on, so Silver makes a lot of sense.
El Chato Nevarez aka, Pedro Nevarez, is widely believed to have raided all up and down the Camino Real portion of the Jornada del Muerto before eventually being captured and put to death in Mexico, where his written confession, or waybill (derrotero), comes from. Travel 4 days by horseback north of El Paso, seek the Caballo mountains, and search for the signs indicated. Two major caches are mentioned: one on the East side and one on the West side, plus a number of other small burials. Springs are mentioned as major signs, and caves contain the major treasure.
Fowler, Wilfred R. Old Spanish Treasures of the Southwest. Many other sources corroborate the basic story, almost down to the exact words, but some contain additional detail or different interpretations from old Spanish.
The Caballo Mountains are entirely public access. Take care to observe obvious mining claim markers, as there is an active placer gold area on the SE side, plus folks hunting down the MANY tales of treasure in these mountains. You can drop down from the North on a dirt road on either side of the mountains from Truth or Consequences (closer to Cutter on the East side). From the South, things are more complicated. You can go up the Jornada itself on the road to Engle, or if your vehicle is more capable, you can come in through the high gap East of Garfield. Searching out the road that you see crossing under I-25 south of Caballo dam is the most direct route – look for the high radio tower on the West side of the river on the frontage road and you’ll get there by driving farm-field boundaries.
The indicated search radius is not the whole area of interest. Basically anywhere in the mountains and surrounding area is fair game. Doc Noss and others like Doughit or Drolte may or may not have actually got into some of El Chato’s treasure, but it could have come from other sources, too. The mountains are FULL of caves and are very rugged.