Conductivity of Gold vs Silver

[GTzer]

I did not do a search yet. Why is gold (even al) described as low Conductivity compared to silver or copper? It's obviously different.
But aren't they all great conductive metals- of electricity? None are magnetic. SO what are the detectors measuring? -resistance, oxidation .......

 

[Digger]

Although the term "conductivity" is commonly used to describe target properties, what the detector is looking for is the target's "time constant". A targets time constant is comprised of its inductance and its conductivity. If you take a look in the FAQFAQ section listed near the top of these posts, you'll find an articl written by Bruce Candy of Minelab that has a lot of interesting information concerning this very subject. HH Randy

Metal Detector Basics and Theory --- paper by Bruce Candy
http://www.minelab.com/__files/f/11043/METAL%20DETECTOR%20BASICS%20AND%20THEORY.pdf

 

[GTzer]

As always Randy- thanks for the info & link.
Greg

 

[Big Boys Hobbies]

Although the term "conductivity" is commonly used to describe target properties, what the detector is looking for is the target's "time constant". A targets time constant is comprised of its inductance and its conductivity. If you take a look in the FAQFAQ section listed near the top of these posts, you'll find an articl written by Bruce Candy of Minelab that has a lot of interesting information concerning this very subject. HH Randy

Metal Detector Basics and Theory --- paper by Bruce Candy
http://www.minelab.com/__files/f/11043/METAL%20DETECTOR%20BASICS%20AND%20THEORY.pdf

Great post Digger!

 

[David]

Silver and copper are a better conductivity of electricity than gold and aluminum, and gold is a better conductivity of electricity than iron, and iron is a better conductivity of electricity than wood or rubber, And boy, rubber boots are sure a poor conductivity of electricity, as you probably know what I mean, but if you wore boots made of aluminum you would sure feel the electrical difference first hand.!

 

[GTzer]

David,
Thanks for stating the obvious. Looks like in the MD process there is a more complex meaning along with the electrical conductive properties of the metals. That was one of the reasons for my post. In order of (least) resistance (actually the least,lesser resistance =a more efficient path to conduct electricity) the order would be Silver,copper,gold aluminum. All 4 are great conductors of electricity and in a general sense -interchangeable- that is- Al is used instead of copper (due to cost) for the power line coming into your house.
Because it "oxidizes" into a more brittle form than copper- it has been outlawed for "in house" electric. Because gold doesn't oxidize it can replace silver in certain high tech and harsh environment applications.
All being great conductors-I couldn't imagine that a MD could detect such small variations in electrical conductivity alone. And they don't.
And they actually do make conductive rubber -now days- but I get what you were trying to say.



Great link. Thanks Digger.