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osbod007

Yankee Fork Gold Dredge And Tailing Piles

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I've been looking at the spec.'s on this dredge and it shows the trommel classifier to have holes of a maximum of 5/8 inches.  This dredge was built and put into service around 1939-1940.  I would believe that the late date of manufacture and historic operating experiences would have dictated the design spec.'s to recover the vast majority of the gold available. That said the larger gold would have been ejected out of the fan tail in the pilings mix.  I have detected tailing piles north of Fairbanks with my Tesoro LST and due to the low mineralization and favorable conditions I was hitting 22 lead at around 10 inches but no gold.  A target greater than  3/4" is sizeable so I would presume maximum depth and large area coverage would be the best plan for recovery. That along with a coordinated dozer push to keep the overburden to depths of less than  2'  I think would be ideal. My question might be which detector would be best?   Low mineralization and targets greater than 3/4" and large area coverage.

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Do you want depth or discrimination?

For depth I'd be using a GPX 5000 with an 18" round mono coil.

Discrimination I'd be using a Equinox with 12" x 15" coil or Gold Racer/Gold Kruzer with 13" x 15.5" coil.

Just my choices... there are many others that would work also.

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Discrimination not so much, in these tailings piles depth and area coverage would be my preference.  I have watched a number of vids posted from down under where they have a very large PI coil attached to a GPX5000 and this arrangement being pulled behind an ATV. Looks humorous but the results seem to speak for themselves.  The nox in all metal with a really large coil would probably be the ticket except for the pendulum weight factor having to swing it over a very large area of landscape. (yes, I know, I'm a whimp). 

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The Yankee Fork is small gold country. I don't think I've ever seen a nugget from that area, definitely not anything bigger than 5/8". Not to say there aren't any but I would personally be looking at other areas for detecting. 

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IDdesertman,   Sorry for the misleading intro. The gold classifier of the Yankee Fork Dredge may be for small gold. My interest is North in the Fairbanks Alaska Goldstream Creek near Fox where the old Gold Dredge No.5  operated and still sits.  It is possible that the trommel classifier in No.5 dredge may have been sized for larger gold. I have not been able to find the spec.'s of the trommel to know for sure. I     do know that larger gold did exist and exited with he tailings. The tailing piles are still all 'active' claims. 

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To be honest i never thought about the size of the trommel classifier thats very smart lesson learnt....

 

RR

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19 hours ago, osbod007 said:

The nox in all metal with a really large coil would probably be the ticket except for the pendulum weight factor having to swing it over a very large area of landscape. (yes, I know, I'm a whimp).

Large coils are pretty much going to lead to imbalance in the swing unless a you add a lot of weight to the upper end of the shaft.  But then you are trading weight for balance, which may be a good tradeoff for some but maybe not everyone.

They make a guide arm attachment for the GPZ7000.  This basically allows you to use both arms when swinging the detector.  I don't know if it would work on other detectors but it seems like you could copy the design (and if you have 10 thumbs I bet you have a friend good at mechanical seat-of-the-pants rigging 😁).  There might be other commercial options as well.  You could look at Doc's site (or even call him).  He makes & sells quite a few accessories.

If you're thinking of going with the Equinox, check out Steve's shafts (and you can call him to discuss weight & balance).

 

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26 minutes ago, GB_Amateur said:

Large coils are pretty much going to lead to imbalance in the swing unless a you add a lot of weight to the upper end of the shaft.  But then you are trading weight for balance, which may be a good tradeoff for some but maybe not everyone.

They make a guide arm attachment for the GPZ7000.  This basically allows you to use both arms when swinging the detector.  I don't know if it would work on other detectors but it seems like you could copy the design (and if you have 10 thumbs I bet you have a friend good at mechanical seat-of-the-pants rigging 😁).  There might be other commercial options as well.  You could look at Doc's site (or even call him).  He makes & sells quite a few accessories.

Whats JP use?

 

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GPZ 7000 with a 15"  or 17"X coil, hip stick and MLs guide shaft, Manual GB, pump don`t swing to GB with the QT button, set to Extra Deep. Would be my OZ choice of current detector, coil and operating mode, found over the years thinking outside the box is most productive, our detectors have become mass consumer products, thus operating instructions target new users. The GPZ 7000 has many features that up its capabilities but suggest you master the initial ML operating instructions firstly with its standard 14" coil.

Edited by Norvic
added clarification

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