Not very well at all. The process is called Redox. It stands for reduction/oxidation. It has to do with the acquiring or donation of electrons from an atom. It always happens in pairs. One atom gives up an electron and another acquires it. There is a lot more to it than that and it gets complicated, but that is the gist of it.

Gold does not oxidize easily and tends to neither surrender nor acquire electrons to become ionic.

I am reaching a bit by drawing on my memory of chemistry in college. I just don't don't know the exact reason why gold does not transfer electrons, but the state for gold is very stable, so it just doesn't like to come to the redox party like other metals do.

because gold does not readily ionize, it is tasteless. That is why it makes a good tooth filling or at least on reason why.

The bottom line is that gold is a non-reactive element and does not oxidize.

Most of what you say is true. However, it's realtively easy to form gold ions for electroplating, etc. One simple way is to form (or buy) gold salts which readily dissolve in various aqueous or solvent systems.

Friend -

Thank you for the thoughtful response. Great stuff!

BRUCE

I am drawing on incomplete information. Gold in (SA) mines are found in some or other oxidised state. What were required to achieve that? (high temp or pressure or a catalyst?)

There's a comprehensive academic treatise on the subject here

ASVP - great article...thanks

Actually gold is very reactive as a single atom. It is so reactive that it reacts with itself to form Au2 molecules which are quite stable and do not readily react with other elements. That is why, when you want to dissolve gold, you need a combination such as aqua regia which is a combination of nitric acid and hydrochloric acid. The nitric acid acts as a catalyst and enables the hydrochloric acid to react with the gold to form gold chloride. Gold is usually found in the Au2 form which is why it is commonly thought to be non reactive.

bbergwall,

I do not know the reason for your asking this question. Several good answers have been given. The only piece of information that you may or may not need is that "Gold" is not just Gold, but rather an alloy of Gold and other metals.

In its purest refined state, and even as the relatively pure bullion alloys, it is very non-reactive in most chemicals, particularly oxygen which is known to corrode many metals, however it is attacked directly by some chemicals, particularly strong acids.

The one thing to be careful of, if you are working with a lower karat weight (purity), is that the other metals in the alloy, primarily copper or silver, may oxidize or react with other chemicals, tarnishing the surface of your "Gold" object. Cheap "Gold" jewelery is particularly known for leaving a "green ring" around some peoples necks or fingers. In this case it is the copper content that is oxidizing and leaving some of its green copper oxide on the skin. Some oxides simply turn brown or whitish gray, reducing the luster of the "Gold" object.

Pure gold, usually 99.999% or so, is considered 24K. It is far too soft in this state to be usable for jewelry or anything needing mechanical strength. So it is alloyed with copper, silver, or other metals to make it stronger, usually as 18k or 14k, and sometimes 10k. 10K is often used for the least expensive jewelry and is the strongest alloy usually used for that purpose, however it is also most easily corroded when immersed in strong chemicals.

The other metals can also subtly change the color of gold, with copper producing a more reddish gold and silver producing a more greenish gold tint. There is also white gold, which is not so subtle, but has a silvery appearance, as well as other tints such as blue and purple.

I hope this helps.

Non omne quod nitet aurum est.

That's another axiom shot down!

"Non omne quod nitet aurum est."

Is this, "All that glitters is not gold"? That saying primarily refers to the mineral pyrite, or iron pyrite, which is iron sulfide, FeS₂, and which has a golden glittery appearance, not unlike some gold ores, hence it's common name "fool's gold", although it usually has absolutely no gold content (unless it is a trace amount). However, sometimes pyrite is found with a small amount of gold content and can be a valuable gold ore, from which gold may be refined.

Perhaps, in light of my earlier post on purity (and therefore value) of different gold alloys, the saying should be "All that is 'Gold' may not be golden!"

I don't think Chaucer had Iron Pyrite in mind! Actually, I was thinking more of Shakespeare - "All that glisters is not gold." - as a reference to the purity of gold these days.

Perhaps Shakespeare was quoting Chaucer! Anyway, "glister" or "glitter" makes no difference in the meaning:

glister

One entry found for glister. Main Entry: glis·ter
Pronunciation: 'glis-t&r
Function: intransitive verb
Inflected Form(s): glis·tered; glis·ter·ing /-t(&-)ri[ng]/
Etymology: Middle English glistren; akin to Old English glisian
: GLITTER
- glister noun

Shakespeare's point was more one of don't judge by appearances. (Luke)

"All that glisters is not gold;

Often have you heard that told.

Many a man his life hath sold,

But my outside to behold.

Gilded tombs do worms enfold."

STL - Thanks for all the great info. Question: Is there a "best" metal to combine with gold to make it the most suitable for manufacturing - electrical connections?

Cheers

When I worked for 3M Company manufacturing the Scotchflex Interconnect System for flat ribbon cable, the connector material of choice was berylllium copper, with selective plating of "hard gold" (Au-Ni or Au-Co) over Nickel in the contact area and a "flash gold" (very thin) cosmetic 24K plating overall. We also used Tin-Lead plating on solderable terminals. Phosfor bronze would be second choice after Be-Cu.

Gold is just too expensive to use as a connector material itself, rather than just as plating. If gold-plating over copper did not perform as you wish, try gold-plating over silver.

The Saying should say "Gold is virtually Forever" not "Diamonds are Forever"

Diamond will oxidize not as 'rust' but vapourise into individual carbon molecules.

Gold nearly lasts forever, just don't touch it, or breathe on it or wash it.

Gold nuggets found (in Australia, anyway) that have accreted in sand, usually have a high percentage of silver (still in some debate) whereas reef gold is in it's more pure form as it has usually just percolated up from a cooling granite pluton.