Gold pans & The Kress Hypothesis

This is all about the slope angle of a gold pan wall , seeing there are a lot of blokes here who know a hell of a lot more about pans then me I'd like some opinions please , is this a crock or correct ? :/ ?

GOLD PAN and the Kress hypothesis
The importance of the angle of slope of the circular wall is implicit in all US patents for gold pans, but only in the 1950s did any inventor properly examine the effect of the slope on panning performance. It was Bruce Kress who first developed a hypothesis for wall slope in 1957 in US patent #2,797,809. The Kress hypothesis might be reworded as:
The angle of inward slope of the circular wall of a gold pan should be in the range of 18 to 26 degrees; less than this and the contents of the pan are likely to remain inert, more than this and the contents of the pan are prone to collapse regardless of the size of the particles or their density.

If the Kress hypothesis is correct, then the majority of North American pans have outer walls that are much too steep for ease of efficient use. Yet thousands of recreational miners, prospectors and geologists continue to use steep-sided pans. Possibly the Kress hypothesis is erroneous; more likely the hypothesis is correct but compromised by the overriding desire of the panner to have a central flat area of maximum size to contain the maximum ore and water during the initial wetting, disaggregating and sorting. Only in the later stages of panning does the Kress hypothesis become critical, after the volume of solids and water in the pan have become greatly reduced. Tests and detailed observations are required. In the 50 years since the Kress hypothesis was propounded; more than 10 North American gold pans have been patented but all ignore it.

More info here ~ http://www.mine.mn/Gold_Pan.htm

The link makes for interesting reading ... can see where many of 'todays' innovations, with slight variances, came from, once again everything old is new again.
Thanks for posting, Tom

People around the world use all sorts of dishes to pan for gold. The American pan as we know it is only one of many. I have seen pictures of locals in Africa using pans that don't look anything like what we are use to. They also work.



Or this one in Asia. I think you can pan with almost any dish that's similar in shape.

Thanks to who commented .

Seems no one knows if the Hypothesis is correct , I suspect it is but I'm to dump to figure it out for now , I'll incorporate his thinking regarding these angles into what I'm up to & hope it works out better :8

My personal opinion only the angle of the wall has absolutely nothing to do with stratification. Stratification is what we are trying to achieve in a pan then we let gravity do the rest.

We help gravity by adding pressure breaks to prevent fines washing out via scraping on a smooth surface.

Ive panned with everything from $2 salad bowls to well every pan ive come accross i would say is have 45 pans easily what varies mostly is quality of plastic and uv stabiliser and size of riffle the pitch i cant see plays a role in todays pans as we dont have slick bols