Anywhere you pull off the road in the mojave desert is a good spot to look. I would pull off the road and head to any of the hills and get out and pound the ground. There is so much to find out there, it is very rich mineral wise- also a barrel full of lost abandoned mines to search.
The nice thing about the desert is that the ground is somewhat bare right now and you can see the minerals on the surface. Try any of the gullies or washouts for crystals, geodes, etc. There are many books on the subject including the Karl von mueller TH books, and "Gem trails of southern CA" by James r mitchell.
If you check the tortoise holes they tend to drag things to the surface as they dig.