What to look for is a concentration of the metal. This can be found in quartz veins that have had a secondary enrichment of gold, (after faulting and reoccurrence of hydrothermal activity ). This can be recognized by a porous seam adjacent to the vein. These solution seams can be yellow, red, or dark in color... they are notably visible as a change in the host rock next to the quartz vein. The quartz in these veins is cracked and fractured, providing the spaces for gold to accumulate. The east belt of the California Motherlode and the epithermal (surface) veins of the desert are good examples of the secondary enrichment that can occur in gold quartz veins. ... Quartz stringers, ( small narrow veins that are sometimes only an inch or two wide with many turns) can be rich with the metal. While metal detecting in the desert in 1994 with a good friend and fellow geologist, we discovered a 40 ft. epithermal stringer that yielded a small fortune in gold and silver. ... Pocket loads are the true bonanzas that can still be found by metal detectors. These are nearly vertical gold quartz veins that erode down upon themselves. The only evidence of their presence is a dimple or swale in the surrounding ground. These are the deposits that dreams are made of ... and that the avid desert detectors hope for. These deposits literally look like someone dumped a bucket of gold in a hole, and yield fortunes instantly. ... The famous Lost Dutchman's Gold probably came from one of these pocket loads, and this is why, to this day no one has relocated the deposit... yet.
Tip: Bends and turns in a vein are the most likely places for gold to accumulate. In the formation of veins, as fluid silica, (quartz) passes a corner it creates a static charge, and this in turn creates gold deposits.