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doc holiday

Why Is Gold A Low Conductor And Silver A High Conductor When

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Hey Doc.  Gold silver and copper are all very good electrical conductors because of their atomic structure, in a individual atom they all only have one electron in their outer orbit.   Lead has four electrons in it`s outer orbit and doesn`t conduct electricity as well as the other three.  Here is a description I found for why different materials are used "Conductivity refers to the ability of a material to transmit energy. There are different types of conductivity, including electrical conductivity, thermal conductivity, and acoustical conductivity. The most electrically conductive element is silver, followed by copper and gold. Silver also has the highest thermal conductivity of any element and the highest light reflectance. Although it is the best conductor, copper and gold are used more often in electrical applications because copper is less expensive and gold has a much higher corrosion resistance"

https://www.thoughtco.com/the-most-conductive-element-606683

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Phoenix thanks for your informative reply and links.

I guess what I have trouble comprehending is why if gold is such a good conductor of electricity it comes in as a low conductor on a TDI detector and silver comes in as a high conductor.

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My bad mate, I mis understood your question. I hope somebody can answer it for you. Dave

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Gold is a good but not a great conductor of electricity. Copper and silver are better. People assume gold is better because they see it being used in electronics, but that has less to do with its conductive properties than gold's ability to withstand tarnishing or corrosion.

From http://www.mains-cables-r-us.co.uk/blog/2011/11/20/the-conductivity-of-metals-used-in-hi-fi/

Conductivity.jpg

Even this chart is based on pure gold. Gold alloys have far poorer conductivity than pure gold, and so the difference is much greater for alloyed jewelry gold and natural gold.

From https://www.911metallurgist.com/copper-electrical-conductivity/

 what-affect-Copper-Electrical-Conductivi

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Conductance is a simple way of explaining the difference in metals, but what really matters is the metal's ability to generate, and hold a magnetic field when current flows through it.

Jim

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Thanks guys for your replies--

Jim your reply,I believe, explains more closely what I am trying to comprehend,EXA. On a PI detector the the return from a gold nugget is much shorter than from a silver coin,hence, is this why a nugget is considered a low conductor and why does the nugget have a short "time of return" if gold is such a good conductor?

Thanks for any replies to this.

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Doc… you are comparing an ideally round shape in the form of a refined silver coin that readily supports induced eddy currents to naturally occurring nuggets that  usually target ID as low conductors because for various reasons they are not ideal candidates to support induced eddy currents. Why is that the case??

How well a nugget will support eddy currents, and generate whatever signal strength and target ID will depend upon physical / chemical parameters such as size, shape, purity, types of mineral inclusions, structure (for example… dendritic, plate, disseminate or particulate, sponge, nuggety or massive), and the profile presented to the coil. Such factors are invariably less than ideal to support eddy currents, and hence testing nuggets of differing size, shape and structure will produce a variety of PI time constants.

See the comparison photo of silver examples below, but keep in mind that a large portion of our silver ores and nuggets do target ID within the foil to nickel range. Small nuggets, similar in size to those in the photo, that target ID in the silver dime range are relatively quite rare.

Ground conditions also play an important role determining in-situ target ID, and refer to factors such as the strength of non-conductive magnetic susceptible iron minerals, ground moisture content, proximity of adjacent targets, and disturbed ground. These factors occasionally contribute to perfectly good silver nuggets and ores at depth producing a VLF target ID in the iron range. Hope this post helps... Jim.


20180129_170556.jpg.30fab1045d2fd5f88954acd324ca27cc.jpg

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11 hours ago, doc holiday said:

Thanks guys for your replies--

Jim your reply,I believe, explains more closely what I am trying to comprehend,EXA. On a PI detector the the return from a gold nugget is much shorter than from a silver coin,hence, is this why a nugget is considered a low conductor and why does the nugget have a short "time of return" if gold is such a good conductor?

Thanks for any replies to this.

Doc, if you look at this chart, you can see the difference in magnetic susceptibilty. Silver is about 50% higher than gold. When you add in what Jim H. said, you can see why nuggets are more difficult to detect. This chart also shows why pulltabs and aluminum cans are so easily detected.

Jim

Magnetic_Susceptibilities_of_the_Elements.pdf

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