GB_Amateur

It's nice to see experimenting with settings and using one's head pay off.  Nice effort, Mark.

I might have missed it here (or in your other post about hunting in ground inundated with coal cinders), but what coil(s) are you using?

This has me wondering:  what is the most valuable coin ever found with a metal detector?

Here's the full story about the fire that destroyed the Chatanika (FE #3) dredge:

https://www.adn.com/alaska-news/article/piece-fairbanks-history-preserved-time-goes-smoke/2014/02/10/

19 minutes ago, GB_Amateur said:

Does anyone know the last 36 year history of that dredge?

Trying to answer my own question.  Is this it?  https://en.wikipedia.org/wiki/F._E._Company_Dredge_No._4

From the 1981 KUAC copyright on the YouTube page and the deduced price of gold at the time of narration ($500,000/1000toz) which is consistent with 1981 values, I conclude that the soundtrack was added that year.  Does anyone know the last 36 year history of that dredge?  It looks to be in pretty good shape sitting idle in 1981, at least compared to the two bought by Tony Beets on Discorvery Channel's Gold Rush show.  I think he paid ballpark $1M each for those.  They are located in the Canadian Yukon.

Interesting & informative video.  I kept wondering how often those laborers suffered injuries -- not exactly OSHA approved conditions by today's standards.  But just part of the risk to make a living in Fairbanks area in 1949, I'm sure.  Good stuff.

10 hours ago, Steve Herschbach said:

Earbuds like I have which have no volume control of their own only work with detectors that have a volume control. If your detector does not have a volume control, get earbuds that do.

The Deteknix W6R6 (Transmitter & Receiver pair that allow you to use your own headphones) have a volume control built in.  It won't let you select an independent volume for each ear, though.  I think the new Garrett Z-link T&R has the same feature.

And thanks for the Ebay link to those earbuds, Steve.  I just ordered a pair!

On 4/1/2017 at 10:25 PM, Steve Herschbach said:

While not quite as hot on small gold as a Fisher Gold Bug Pro or Teknetics G2 at 19 kHz the Patriot at 13 kHz I have no doubt can perform reasonably well at nugget detecting....

Here is a statement from the F70 manual:

The Autotune mode is more sensitive and offers better feel than the Discrimination mode, and is used to find all metal objects present in the ground. The search coil must be in motion for objects to be detected. This is a single filter search mode similar to the “fast autotune”, “SAT”, or “P4” mode found in other detectors you might already be familiar with.

And here is a quote from Dave Johnson on the Fisher website:

Most VLF prospecting is done in an all-metals mode which may be variously described as "single-filter", "first derivative", "autotune", or by trademarked names.

I was under the impression that First Texas held off the single filter all-metal feature from the F70 so it wouldn't compete with their more expensive T2/F75 models, but it looks like I was wrong.  If that's the case, and if the Patriot is just an F70 in modern dress, then the Patriot should do as well as the T2/F75 while prospecting, with possible exception of the "Limited" editions which have extra sensitivity with their "Boost Mode" option.  Am I reaching the right conclusion?

On 3/25/2017 at 9:35 PM, Steve Herschbach said:

Well all I can say is it is about time. The norm in most consumer electronics is a rapid move to more power at lower prices. The metal detector world moves very slowly by comparison, and if anything the average price has gone up in the last 15 years. First it seemed like over $1000 was a lot for a detector. Then it was over $2000. And who ever thought we would be seeing consumer type detecting devices going for over $5000!

I was thinking about this the other day while driving.  In summer of 1979 I bought a new Garrett GroundHog with 8 inch coil for ~$800 and then paid another $100 for the big coil (11 inch round coplanar).  The US Consumer Price Index was 74 then and about 244 now -- a factor of 3.3 increase in 38 years.  So that $800/$900 outlay in '79 translates to $2500-$2800 today -- about the cost of a Minelab CTX-3030 or GPX-4500.

I was looking at a used detector this morning -- $550 price tag, and I thought "that's a lot of money".  I make 4x what I did back in 1979, and I don't think I blinked buying that Groundhog.  Funny how our views change with time.

8 hours ago, tboykin said:

Thank you guys for all of the feedback. I always feel bad digging a big ole plug in parks. I will try and work on my screwdriver skills.

One of the things I've read over and over regarding general detecting:  don't have a locked mode of setting your detector, but rather adjust to the situation you are in.  IMO this applies even more broadly to park (and other public property) hunting.  I've been in situations where strict rules (e.g. no plug, no serated digger) were enforced.  I've also been in other locations where plug cutting (with "catch-and-release" = "leave no trace") was allowed.  Best is to have all of these options/skills in your detecting toolbox.  1% of the public will take offense no matter what you do.  The other 99% will notice and be tolerant because of how well you respect the land.  I lean to the side of catering to the 99%.  Follow the rules, but when they are vague and/or allow interpretation, take advantage of that.  Just be a good citizen in the process, and follow the Golden Rule.

I'm a southpaw, too (hopefully those not from the US and not baseball fans can figure out the meaning of this from context, or failing that just Google it), but I haven't noticed detectors being particularly biased in this aspect.

What I like are:

1) lightweight AND balanced,

2) pushbuttons over knobs (this one definitely seems to be personal preference),

3) settings saved when turned off,

4) Keep It Simple, Stupid (KISS).

5) User control of ground balance (at least automatic and preferably manual adjust).

I don't know that there is yet today a detector that perfects all of the above, but there are several that are close.

A lot of us have been excitedly watching a few teasers on soon-to-be-released detectors here.  Regarding the Nokta Impact, has there been a conclusion reached on whether or not it has a true, pure, (near-)analog all-metal mode?  If we're still awaiting hands-on testing, I'm fine with that.

2 hours ago, tvanwho said:

We depend on our electronic toys too much these days in my opinion.

A quote I've remembered since the first time I heard it, over 40 years ago:

I can't say as ever I was lost, but I was bewildered once for three days.

Anyone else remember that, and who said it?  (No fair cutting and pasting on Google.)  Hint:  If you were ever lost in the wilderness and had a "phone a friend" available, this would be the guy to choose.

I use Google maps/earth to make hardcopy maps to take along, marking geo coordinates on them, especially a couple landmarks.  Then use handheld GPS when in the field.  Also, don't forget to use the sun's location and time-of-day to get a feel for what direction you are going if you don't have a compass or (like me) don't know how to get your handheld to show compass directions. 

On 3/20/2017 at 11:53 AM, Steve Herschbach said:

This is the model without manual ground balance, ground grab only and 5" coil, that normally sells for $499. Every bit as good as the $649 Gold Bug Pro, just lacks that manual ground balance. At $337 I had to fight the impulse to buy one just because the price is so low for a decent machine.

Had mine out yesterday with three coils (First Texas 7in x 11in, Coiltek 6in round [prototype], and stock 5in round).  I also own the Fisher 5in X 10in and Nel Attack 15in, but didn't take them along yesterday.   I really like that detector.  7x11 and 6in coils were picking up some EMI, which didn't bother me when I was swinging, only when I put the detector down to dig.  5 in was quiet.  That's the first time I've ever had EMI noise with the Gold Bug Pro.  Most of the time I use the Ground Grab, but occasionally tweak with the manual adjustment option, so that argues a bit for the Pro model (although what one is willing to pay for that feature is certainly an issue).

On 3/20/2017 at 11:53 AM, Steve Herschbach said:

They also rolled the $599 Teknetics Gamma 6000 (a coin detector) back to $356, a huge price reduction.

I thought the MSRP on that one used to be $499....  I've seen them at Bass Pro Shops for that, and recall looking up the price on Teknetics home webpage, but that was a couple years ago.  I've used the Gamma some for coin hunting, and it's a nice detector, similar to the Gold Bug in many ways (no surprise since engineer Jorge Saad has written about the evolution of the Frat Brothers + F5 + Gold Bug lines).  Unlike the Gold Bug and its nearly identical siblings (F19, Tek G2 and G2+), the Frat Brothers (Tek Omega, Gamma, Delta, and Alpha) can be operated with concentric coils as well as the DD's. 

I recall last year Teknetics had a fire sale (only through certain dealers, not widely advertised/facilitated) on the Omega 8000.  That was announced here by one of the chosen dealers.  Seems like it was somewhere in the low to mid $400's.  Also you recently highlighted the Teknetics G2 (Fisher Gold Bug Pro's maternal twin) sale, which was quite a deal, too.  Then there are the current First Texas's sales on their top level detectors (Fisher F75's and Teknetics T2's) which you detailed recently.  Good time to be looking for a high quality VLF detector for at or under $500, and just in time for Northern Hemisphere Spring & Summer.

3 hours ago, fredmason said:

The BLM thinks that old trash is sacred...

I think the cutoff is 100 years of age -- if a relic is younger than that, the 1979 law doesn't apply.  Also, I'm pretty sure coins are exempt, regardless of age/date.  Bottom line is (if I'm right -- I'm not a lawyer so beware) a 1936 can should be ok to keep if found on fed land prior to 2036.  (Doubt I'll still be detecting&digging then, although it's not impossible...)

2 hours ago, kiwijw said:

locations are WHERE GOLD HAS BEEN FOUND BEFORE. I will be the first to admit that it is not true prospecting as the old timers were the true prospectors. They were the ones who found these locations & proved there was gold there.

What the 19th & early 20th century prospectors/miners lacked in technology they made up for with motivation.

Impressive haul, and great job presenting with your photos.

Do you know what those gears are from?  I've found some very similar objects (two today, in fact) and have been leaning towards clock parts.  But who carries around clocks (other than pocket or wrist watches) in the field?

Jason, I'm impressed with your ambition to think outside-the-box, even to the level of building instruments to solve problems.  Please keep us (well, me at least ) informed as you move forward.

(As usual) I don't understand something.  You talk about lithium carbonate as a native ore/compound.  In my (simple) searches I've only seen four primary, cost effective sources of lithium, all minerals:  spodumene, lepidolite, pentalite, and amblygonite.  The first three are silicon based and the last phosphorous based -- no carbonates.  Is the lithium found in these dry lake beds a different form/chemical compound?

Here's a 1/2 inch (12.7 mm) diameter sodium line notch filter for $77 (but says "overrun, out-of-stock").  I don't know if that's a large enough aperture for your application.  I'm sure you can get bigger ones but the price could go up non-linearly.

http://www.omegafilters.com/a5-sodium-line-notch-filter.html

21 hours ago, jasong said:

What technique do people employ to prospect for or test for lithium in the field? A handheld XRF probably won't work on the low atomic number elements. Flame test probably won't work since I'm guessing there is a lot of sodium evaporites on the lake beds in much higher quantities than lithium.

Jason,

Agree that XRF spectroscopy won't work, but why is sodium such a problem for a flame test?  I'd think you could buy a notch interference filter made specifically for eliminating the yellow lines of sodium.  (For those not familiar, an optical notch filter works similarly to notch feature on metal detectors -- target a specific frequency to selectively either include or, in this case, eliminate from the signal.)  Maybe I'm oversimplifying the problem....

Very well written article by a 20-something -- gives you confidence that good journalism is going to continue for at least another generation.

I don't know much about Fenn and am not that interested in going further.  But he has created quite a microcosm.  People becoming overconfident and suffering from confirmation bias (several mentions of that in the article).  People playing results (ex-wife and daughter of man who died looking for the treasure blame Fenn and say the treasure is a hoax; wonder if their views would have been the same had he found it).  And not the least -- people refusing accountability.  He's not holding a gun to anyone's head making them go search.

4 hours ago, Shelton said:

No stereo only one channel. This set doesn't work with stereo mixed mode machines... like Spectra or Nautilus...

Hmmm.   I have both the W3 (headphones) and WR (Transmitter & Receiver with 1/4 in. jack so you can plug in your own headphones) and both work in true stereo mode when hooked up to my hifi (music).  So why they don't work in stereo mode on your detectors leaves me scratching my head.  I've used the W3 with all three of my detectors, but the WR model with only the Minelab X-Terra 705, so far.

13 hours ago, mn90403 said:

The composition of the one on the left is not known to me yet.

Did you (or do you have a way to) measure its density (~specific gravity)?  I do this all the time with finds to try and figure out what they are.  I just read an article by Kevin Hoagland describing the process, and Chris Ralph has also described it (probably in ICMJ).  It's just an application of the Archimedes principle.  Basically you weigh the piece first.  Then hang it from a sling, attached to a scale, and suspend under water, not letting it touch the walls of the container holding the water.  Divide the first (dry) weight by the second (immersed) weight and you've got the specific gravity.  (There are some adjustments that need to be made, for example to account for the weight and volume of the sling.  But if you don't do that and the sling is properly chosen -- very fine wire or thread -- you still get a decent answer.)

Fortunately, the valuable metals in their pure = elemental form can in most cases be distinguished from the common metals.  (Alloys are a tougher road, though.)  Here are some examples of specific gravities by my named category groupings with Troy ounce prices (some outdated) in parentheses.  If no prices then not valuable or better said "not known to be valuable by me."

Super Heavies:  gold($1210), platinum($960), osmium($400), iridium($745), tungsten, rhenium($86) -- all > 19.

Heavies:  lead, silver ($17.40), ruthenium ($40), rhodium($920), palladium($773), molydenum -- all between 10 and 13.

Moderates:  copper, zinc, nickel, iron, chromium, bismuth, manganese -- between 7 and 10.

Lights:  tin, antimony, titanium, vanadium -- between 3 and 7.

Ultralights:  aluminum, magnesium, beryllium -- < 3.

The reason I bring all this up here is because there is a thriving(?) branch of the jewelry business which makes and sells wedding bands in 'exotic' metals.  I found a titanium wedding ring (not valuable), for example.  It was stamped 'ti' inside.  I don't know how many of the valuable metals are or have been used in jewelry other than the obvious gold, platinum, and silver, but I wouldn't be surprised if some, such as palladium, are.  If the density is above 10 and it's not lead, tungsten, or molybdenum you likely have something at least moderately valuable, and if not silver, ruthenium, or rhodium could be very valuable.

Wow, I'm impressed that the CTX3030 can ID those rings with a drill bit running through their centers. 

15 hours ago, mn90403 said:

These are two cheap rings and one more 14k gold ring with a silver band.

I'm guessing the middle one is the 14kt.  What is the composition of the one on the left?  And how did you figure it out?

16 hours ago, Steve Herschbach said:

The Vision/V3i upped the ante but while amazing on paper suffers from interface overload.... Feature overload is not a plus.... The V3i... needs a simplified interface....

(Fantastic article, BTW.  Hope I didn't distort what you said by cutting out some other included comments.  Just wanted to focus on this one issue.)  First off, I didn't notice you mention the VX3, which I guess is because it is such a close variant of the V3i, but I thought the interface was simpler.  Secondly, does a user need to wade through (either on setup or during use) all the features of the V3i, or can he just pick the ones important to him and leave the others alone?  That would effectively simplify things.

The fact that you didn't go into any of these things I just mentioned makes me think 1) I don't understand the concept/meaning of 'feature overload' and/or 2) my (simple) understanding of detectors doesn't come close to how the V3i works.  Please, someone out there clear up my confusion.