I found these documents during my research on building a custom highbanker. Thought it would be useful info for others.

All of these are publicly available at http://www.geology.gov.yk.ca

Miscellaneous, Placer Gold Recovery Research: Final Summary, R. Clarkson, P.Eng, New Era Engineering Corp., 1990, YGS/DIAND. Shelf No. 9-12 http://ygsftp.gov.yk.ca/publications/tech/placerrecovery.pdf

Miscellaneous, An Analysis of Sluicebox Riffle Performance, R. Clarkson, P. Eng - New Era Engineering Corp., 1990, YGS/DIAND. Shelf No. 9-11 http://ygsftp.gov.yk.ca/publications/tech/...ysis_sluice.pdf

Miscellaneous, The Use of Radio Tracers to Evaluate Gold Losses at Klondike Placer Mines, Randy Clarkson, P. Eng, 1988, YGS/DIAND. Shelf No. 9-9 http://ygsftp.gov.yk.ca/publications/tech/the_use_radio.pdf

i sent off and bought three of the videos(VHS) that they offered. it wasnt cheap but it did give a lot of insight! they were ava. from: AM Productions inc. 48 East 6th Ave. Vancouver, BC Canada VST 1j4 or email at: info@amproductions.com their websight is: www.amproductions.com they have a lot of different videos they offer. also thankyou for these links. i put them in my favorites for future referance.