Black sand streak with Gold Scorpion

[sluicedog]

I need some instructions on using my gold Scorpion to locate black sand streaks in a river bed. Tips on ground balancing (I'm slightly positive for small gold nuggets), Sounds or lack of sounds to listen for and maybe sweep speed. I have two coils, 5X10 and 4 1/2' diameter. I hunt in the all metal mode and I have a Depth Master sound enhancer w/ ear phones attached to my detector.

 

[Fishers Ghost]

Set the detector to the All Metal GB mode and adjust the GB to as exactly for your ground as possible.
Any black sand that is denser than the ground you have GB over will respond as a positive tone in the HPs.

When looking for black sand donot scan the detector left to right but simply walk straight forward with the coil held out in front and an inch or two above the ground.
In this way you will find the highs and lows of the concentrations of the black sand and will be able to map out the run of the sand.

The detector will not respond to black sand at great depth, so you will not have to dig deep holes ( no deeper than the diam of the coil you are using) in order to locate any sand that has caused a signal; if the signal does persist to a deeper level then you may have found a larger deep conductive item, in which case dig until you find it??

You can use the scorpions Calibrated TR Disc mode to ID any rocks that give a positive signal as per the manual.

 

[salmonriverhotrock]

Here is a read that may help you. Below is an out take from the link.

http://www.losttreasure.com/content/archives/garrett-electronics-scorpion-gold-stinger

My wife, Rosanne, and I return to this stream planning to use the Scorpion to locate potential areas to bring our dredge in at a later date. Rather than using the detector to locate metal targets, I intended to use it to locate pockets of black sand which often contain gold.

With the 16-turn ground-balance control and the manual audio threshold tuning mode, the Gold Stinger was ideally suited for this application. I used my gold pan to sample a gravel bar located in the stream and determined that, while there was a little black sand present, it would be a good spot to "calibrate" the detector for my search.

Setting the Depth control to Preset, the operating mode toggle switch to All-Metal, and the tuning toggle switch to manual, I preceded to ground-balance the Scorpion. When searching for black sand deposits, I found it preferable to run the audio level slightly higher than normal in order to hear any change.

Slowly scanning likely looking spots, the audio threshold suddenly decreased noticeably, indicating the presence of an increased amount of ground mineralization which is usually caused by a concentration of black sand. Filling the gold pan with a sample from the area and panning it down showed that not only was there a fair amount of black sand present, but a number of small gold flakes as well.

 

[salmonriverhotrock]

What I have is a Garrett ADS Ground Hog that is one of the Grandfathers to the Garrett Scorpion. It has been some time ago that I've set it up for locating Black Sand Pockets but it will find them and is why I quickly gathered enough magnetic black sand to make myself a Test Bag. In the old book "Electronic Prospecting" by Charles Garrett and Roy Lagal, they suggest you gather about a gallon of black sand in a bag but I get by with a Pint.

When I get the ADS Ground Hog all set up and ground balanced over ground not containing any metallic items or Hot Rocks, if the search coil passes over any metal or Hot Rocks, it should sound off. If passed over the bag of black sand, it will "NULL" out. The same should occur out in the field over black sand pockets that sometimes are distinguished by visible hints of black sand. Now if you advance the Ground Cancel (positive) a turn or more, the metallic item(s) should still respond and when the coil is passed over the black sand, the sand should now respond. So that you know, the Ground Cancel control on the ADS is a 10 turn control. In some cases, I have found I can turn the Ground Cancel positive as little as 1/4 to 1/2 turn and get the black sand to sound though a turn or more is suggested. If the area you are going to search is anything like here in Idaho, you will have to deal with Hot Rocks and metallic trash in the rivers and streams. That is one reason I run with a normal Ground Cancel adjustment so if it Nulls out, it is either a Cold Rock or a black sand pocket though you should investigate all metal sounds. A typical Hot Rock will detect and sound with a smaller length and width coil swing where a black sand pocket may sound wider and longer in relation to the coil swing. My ADS Ground Hog has three coils and all are Concentric coils and for black sand, I use the standard 7 inch coil and the bigger 10 inch coil and then the small 4 inch for tight places, trashed out places, and getting up near metal posts, buildings, and such. .

Now if your Scorpion has a Concentric Elliptical or a Elliptical DD coil, it may handle black sand much differently than I described above and you will have to experiment. I have yet to try my Whites GM V/SAT out on locating black sand pockets. On top of that, it has a 40:1 Ground Balance control and my coils are Concentric Elliptical and Elliptical DD coils. I hope this helps. Just remember, where you find Gold, you find black sand but where you find black sand, you will not always find Gold.

 

[sluicedog]

Robert-I have a big container of black sand from the river and will put some into a big flat tub to hear tone drop. I have the 3/8 gravel from the same area to make a test bed. Hopefully, I will be able to hear the subtle difference in the sound(Depth Enhancer on and/off).

If I ever find enough gold I might consider a Whites GMT(my budget range) High Frequency and Visual display for black sand streaks. My two Garretts(Scorpion and XL500 PI) would work great if I was in our western States were the gold is larger to be picked up by the coils and machines.

The river in NH (I live in CT) has hot rocks...I'm used to those and discard them with the Scorpions circuitry and setting. The spot of interest has mixed cobble,sand and gravel. The clay layer varies from 1' to 2' in this area. I'm trying to narrow down a spot of black sand streak and use my small dredge to clean down to the clay layer. Gold in this NH stream in flour to fine with an occasional flake and picker/nugget. If I could bucket dredge the whole zone I would...however I would like to use my electronic prospecting equipment to narrow the search. I have flag pickets to help map the zone.

Most machines work great...its the 100 hours plus hours of use and tips from other experienced users that make the finds possible.

warm regards-Bill

 

[salmonriverhotrock]

Something that may help you develope an ear for Gold Nuggets or Pickers is using soft lead like fishing sinkers. Soft lead about the size of a piece of raw Gold will sound and or detect about the same. I have actual Gold pickers that weigh 1 and 2 Grains that I carry out in the field with me to check against the ground and or rock conditions to see how they will detect and to affirm my ground balancing. With my stuff, I also have soft lead bird shot test pieces that weigh about 1,2,and 3 Grains.

Those may be too small for a Scorpion to detect at 15 kHz but you could start out with a .22 bullet (no copper jacket) that I think is somewhere around 2 Grams. Your standard eliptical DD coil should sort of speaking, see through the soil iron and mineral content better than a concentric eliptical but if I remember right, you will lose a bit of depth but that may help you find smaller, though not quite as deep. Try it on the surface of the ground you are going to detect and then bury it a couple inches deep so to see what changes occur and what you will have to deal with. From there, you can go smaller test pieces. If you don't have one, you can get a Jewelers electronic scale with a calibration weight to weigh your test pieces and Gold if you find any.

I have never used a detector over 50kHz. but I have read that there are detectors out there with high enough operating frequencies, that will respond to flour gold in large and pure enough concentrations. I would imagine though that those concentrations are extremely rare today in the rivers and gold areas that have been worked over so heavily and for so many years.

 

[sluicedog]

Thanks Bob-I found making some tuning pieces for ground balancing helps a lot in heavy mineral areas. I bought a Fisher manual and found this tip:
I've made two groups
1)-with poker chips. Drill a 3/8 inch hole in each of three colors Blue,Red and White. Cut a small piece of lead from a tire weight. Put the largest bit in the Blue, half that size in the Red and half the red size in the White. Epoxy in place. Keep in pocket until needed. I throw the chip on the ground, Ground balance the machine to eliminate some mineralization while still picking up the lead in the chip. Start with Blue chip and work down to the White chip(smallest lead bit) for tuning. DON"T FORGET TO PICK UP YOUR CHIP!.

Hey, your buddies might not like you stealing chips at the nex card game-go to plan B

2)I Use three color plastic caps-same idea Blue,Red and White caps. glue lead inside the cap with shoe glue. Plus you get to drink your beverage of choice first...Hey no stealing from your buddies cooler for that perfect Blue Cap.

The tuning pieces are really handy ......you will miss less small nuggets will manual ground balancing..and find out you might have missed some with prior off tunes MD.

I am really trying to hone in on the black sand streaks or bands in a river of interest. Mixed cobble, gravel, sand and hot rock above a clay layer. Strong spring floods occur every year! I plan to use flag pickets to map the river area-then dredge a promising spot(quick pan test first).

-Bill

 

[salmonriverhotrock]

The problem with wheel weights is they have tin and other alloys added to harden them. This will cause the lead to detect a bit differently than regular soft lead or gold.

Try to find some soft lead if you can. Out here in the North West, the Les Schwabs tire franchises are going to steel tire weights because of California's excessive regulations on lead. Instead of closing their tire stores down in California and moving them to much more business friendly States, they are making all the other stores in the North West change to lead free wheel weights. Beings the state of Oregon is the largest county in Claifornia, I'm sure they will be next with Washington State on their heels putting an end to the use of lead across the whole Left Coast. It's my understanding that in California, they are already banning the use of lead Pellets for Pellet guns.

Sounds like you are getting the idea of things though and a lot of the fun is learning how to detect what.