There is a great difference between wet and dry prospecting.
Wet prospecting is by far the more useful and the one which will provide the most frequent discoveries this is because you get a much better separation rate of gold from gravel when wet and sent through a sluice box and subsequent sieve or series of sieves. However, this separation rate is much, much lower when dry and the likelihood of expelling gold with your sand or gravel is greatly increased.
Many modern prospectors are heading to the desert first to find gold. This is because gold is much easier to find in the desert. In fact it is one of the best places to look for it, form the perspective of merely just finding it. The gold in the desert regions of America during the great gold rushes was often ignored. The lack of water and the sweltering heat of the sun scorched sands made it too difficult for early miners.
Want to increase your chances of finding more gold when you go to the desert? A great tip would bring water and a pump to wash the material that you find. In fact you can pull gold from the leftovers that others leave behind from dry washing without having to do much searching yourself.