Spring and fall. Wood casts, agate, jasper, chalcedony. Petrified wood specimens from Stonewall Pass B, Site 83. From the turnoff to Site 82, continue up the road for another 0.9 mile. Pull off to the left and park on the flat next to the low hills.
Petrified wood occurs as a cast of soft, whitish silica.
The stuff is very brittle, so be very careful with it. When it weathers out, it doesn't take long for it to dissolve into mush. A little searching and careful digging will get you some very pretty specimens, though. There is also agate, jasper, and clear chalcedony here. Do a little walking and a lot of stooping and you will come away happy.