Micro gold hunting on lake beaches

... or large ones.
Here's a post I made on a UK forum on the topic of metal coil bolts: whether they would work, what's the best metal etc.
[www.metaldetectingforum.co.uk]

Stainless steel is certainly a poor electrical conductor. And a poor heat conductor, too, making it a bad choice for saucepans, you would reason...
{ the Wiedemann-Franz Law:[hyperphysics.phy-astr.gsu.edu] }

Yes, Rick, other CuNi alloys had been on our 'radar' for certain target models, including Monel and Constantan. The latter is readily available in wire form, being 'resistance wire'.
[www.wires.co.uk]
One feature of using a length of wire as a target, is that the target 'corner frequency' doesn't vary with the length of the wire. Varying the length just increases the strength of the response. So it's possible to 'fine tune' the characteristics independantly. We've analysed regular electrical copper wire and got good data, from which we can work out with maths how different metals/wire sizes will behave. So this would possibly be my approach to the ear-ring 'mimic'.



Edited 3 time(s). Last edit at 07/22/2019 09:10PM by Pimento.

Very Interesting....



Edited 1 time(s). Last edit at 07/23/2019 02:26PM by Rick, N. MI.

Some micros jewelry finds.
I find my first gold earring back.
When I look for it I can't find it.
During a lost ring search, I found this little gold earring back. (probably)
This is my first such hit. 11" coil, beach1, fresh water.

I tested this piece of gold with Nokta Pulsedive pinpointer, it doesn't detect it at all.





Timmy

I know some did in fact come with metal bolts and since they move with the coil the machine does notice them.....but can’t they cause dead spots in that very important area on the coil?

No dead spots.
It's true that the important thing about placing metal ( or ferrite ) near a coil is that it doesn't move (relative to the coil). But it also needs to give a small signal, as large signals can swamp the amplifiers etc in the detector circuitry, leading to loss of sensitivity, or complete inability to detect anything.
Machines that did come with metal bolts always had stainless steel bolts. And probably kept the size of bolt to a minimum as well? eg. using 3mm (1/8th inch) diameter, versus a typical plastic size of 6mm (1/4 inch). Not all stainless steels are the same, I've not been able to test A2 versus A4 grade, so I don't know if there's much between them.



Edited 1 time(s). Last edit at 08/10/2019 02:04PM by Pimento.

timmysys Wrote:
-------------------------------------------------------
> Some micros jewelry finds.
> I find my first gold earring back.
> When I look for it I can't find it.
> During a lost ring search, I found this little gol
> d earring back. (probably)
> This is my first such hit. 11" coil, beach1, fresh
> water.
>
> I tested this piece of gold with Nokta Pulsedive p
> inpointer, it doesn't detect it at all.
>
>
> [/ur
> l]
>
>
> Timmy

Nice recovery on the little treasures!

Blood Member of RingKeepers
2020......Gold Rings....73....Misc Gold 1 .......Silvers ...110

The Nokta AU Gold Finder at 56hkz will blow the Fisher Gold bug 2 out of the water on micro gold & it will kill it on depth on small jewery.
That is a fact.
I tested both detectors using 2 Gold Bugs & 2 AU Gold Finders.

Is this white gold earring find significant ?
[metaldetectingforum.com]



Edited 1 time(s). Last edit at 08/24/2022 12:18AM by tnsharpshooter.

tnsharpshooter Wrote:
-------------------------------------------------------
> Is this white gold earring find significant ?
> [metaldetectingforum.com]
> 16613#post3416613


NO..........

It IS a single-post....stud earring; however......... the setting (the part that holds/captivates the diamond) is a fully closed/circumferential/closed-loop of continuity ........ like a small ring! It presents a moderate level of difficulty for detection....especially if in a SALT environment.......and in a SALT Mode.

Tom_in_CA Wrote:
-------------------------------------------------------
> Ouch. I've been "outed". Yup. This
> is the running cruel joke in my sphere /circle of
> beach-storm erosion hunters here : I've seen it
> "as good as it gets". Yet in all these de
> cades, think I've found a single diamond @ ~ 1/3 k
> arat. A few @ ~ 1/4 karat (which are hardly worth
> fretting over for appraisals). So I've concluded
> that : High end diamonds don't like me

Being the gold coin magnet that you are, you really can't complain, Heck you even find gold coins on the beach too [instead of giant diamonds]



Edited 1 time(s). Last edit at 08/24/2022 07:14PM by Cal_cobra.