[Diamond]

I meant to say two hundred million years.

No problemo.

Hakatai Shale Precambrian pollen. Collection technique:

At each sample site, the first three to four inches (7.5 to 10 centimetres) of exposed rock was chipped off, to avoid any surface contamination (the pores in the rock are in any case too fine to allow pollen to penetrate to any significant depth). Then the rock beneath was sampled, taking care to avoid any cracks and fissures. The team opened previously sealed, sterile plastic bags just long enough to allow freshly flaked-off rock to drop in. They quickly resealed them. In addition, the collection was done in winter, with snow at the canyon top and all shrubs and trees dormant.

Great care was taken in the laboratory to avoid contamination. In addition, control experiments were performed in which, among other things, slides were exposed to the air in various actively used laboratories for a total of some 400 slide-exposure-days. Each slide was exposed for between seven and 57 days. In that time, only three possible pollen grains appeared on the exposed slides, although there were many other contaminants found - fungal spores, plant hairs, epitheleal cells (skin tissue), and even cells resembling blood cells. Thus, the chances of pollen from the air falling on to the slides in the short time they were exposed during preparation were extremely small.
http://www.freerepublic.com/forum/a3916e5874705.htm

Cordially,

[Liberal Classic]

Precambrian Pollen

This latter example is instructive because it shows that even when "creation science" is refuted there is an urge to cling to "evidence" favorable to the cause (Austin 1994:137). Burdick (1966) claimed to have isolated pollens of pine, juniper and Mormon tea in samples of the Proterozoic Hakatai Shales in the Grand Canyon, rocks much older than the first appearance of vascular plants in the geologic record. When later, more comprehensive and careful studies failed to reproduce these results, it was concluded that Burdick's work was simply a case of contamination by modern pollens (Chadwick 1981). MTC still leaves the door open by concluding, "The possibility of pollen in Precambrian rocks, no doubt, will remain controversial among creationists."

Source: National Center for Science Education