The fossils you may find are from 30-35 million years old Oligocene age deposits.  Kim Cochran says that there are elems, gastropods, nummulites, echinoids, and bryozoans fossils in this general area.  There are also tortillas, barnacles and diatoms present.  These fossils are not abundant and may be hard to find in quantity. 

The micro minerals are located in vugs of the agate/chert rock.  If you look closely, you may find rare phosphate minerals like clear to pinkish strengite, green wavellite, variscite, golden cacoxenite, brown to yellow-brown jarosite, sharp brilliant crystals and green-brown fibrous hemispheres of dufrenite, pale chartreuse-green spherical globules of kidwellite, brown to black fibrous crusts and spheres of rockbridgeite, white finely fibrous tufts of churchite.  The vugs may also contain hyalite opal, limonite, deep red-brown hematite, barite, goethite, gypsum, or druzy quartz.