dredgemaster, what is involved in modifying a dredge for land operations? Do you build a small pond on a alluvial deposit?
The most common practice is to dig pits close to the river in the dry season and then break the bank and use the dredge to extract and process gravel.
You can use the top sluice with a local built trommel and hopper and 3inch pump while still useing dredge pump to stockpile gravel.
You can use the dredge pump through the FOOT valve and hose with reduced nozzle to HYDRAULIC materials and move overburden on the bank.(think of a fire hose)
These are only a few ways.
Also what did you average in ounces of gold on the Sewa in a good dry season? What's considered a good production rate? 5 ounces gold per day for a dredge or is it more like 1 ounce?
I concentrated on Diamonds in the Mopende area on Sewa and Gofo and Waterfront in Zimmi also on Moa and Mano.
For Gold the cost of extraction is the key and the least overburden to move the cheaper the extraction. oz of gold per day is not a figure I work on but rather yards moved per hour with whatever gold content the depth of N0 5 sand and gravel has added to the depth of overburden.ie: 2yds overburden + 0.5yds No 5 sands + 0.5yds of gravel and divide this into grams recovered, lets say 20 grams would give you 20 grams divided 3yds depth = grams per yard mined.
Somehow having to hold your breath and having to wear a wet suit in swirling and often murky waters can't be the most efficient way to produce gold especially when there are large rich alluvial land deposits to mine. Plus what about snakes and leeches, etc?
You dont HOLD your breath.
The dredge has a compressor and the divers have breathing equipment.
More experienced local divers will use only a hose direct into the mouth as they are not comfortable with the valve system in face masks. Working BLIND at 30 feet in moving water is what seperates the men from the boys.
IF nature has already done half the work for you by washing the gold into the river, then why add to costs and go and dig materials so that you have to transport,wash and recover and extract. Snakes taste quite good and I will continue to eat them.
I a Banka Drill program shows Gold in Quantities worth Land mining then that is the way to go.
Hope that helps.
Dredgemaster
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