Because the metal is used in gold-plated contacts, it's as easy as that. That is a problem, because unlike jewellery gold, gold in electronic equipment is not recycled.
Gold in electronic equipment is not generally recycled because it's cheaper to mine it. Gold might seem expensive, but you can put a ceiling on its price by thinking about what it would cost to reprocess phones in bulk. Currently tens of dollars per phone, for dollars worth of gold. Increase the price of gold, or recover some other valuable materials, and it becomes economically viable.
Gold is absolutely worth recovering from consumer electronics, as is copper and a bunch of other stuff. It's not necessarily worth collecting, but there are plenty of huge piles of e-waste lying around the globe.
One problem with gold recycling is that some simple methods are also phenomenally harmful to both workers and the environment, as they involve dissolving the gold with mercury. From what I've read, some of this stuff gets shipped to countries with relatively weak labor and environmental laws.
Simple fact, Mercury does not dissolve gold.
It amalgamates with certain metals making them easier to collect in one mass rather than having tiny bits all over the place.
Mercury use has very little to do with gold mining or recovery today.
Repeat: I said it's used very little- not that it is never used.
Its much easier and more economical to just use aqua regia to get the gold away from the base metals.
Gold recovery from electronics is done in semi- laboratory conditions and the gold is refined using the same conditions which are a far cry from some guy in the hills digging up dirt and spilling his waste into a mountain stream.
Modern refiners shun Hg.
It's hard to clean up the waste to acceptable levels.
That's a big deal nowadays.
No one wants to poison the environment.
Acid based extraction techniques are much cleaner,easier and more environmentally friendly.
Just like everything else- it comes down to profits and it's just more profitable to use acids instead of Mercury.
Hell it's even more profitable to use cyanide to extract the gold.
I know a little bit about this stuff- AMA?
The mercury used in that process is generally recycled in a closed loop; if it's done properly, dangerous levels don't get into the workers or the environment. Metallic mercury is the least dangerous form of mercury, less toxic even than the ores mercury is mined from.
Unfortunately with high gold prices it becomes profitable to run small operations that don't meet the same standards. Currently it is believed that 1/3 of all mercury pollution comes from illegal gold mining [0].
I recently donated old electronic equipment to Tokyo city government. Their plan is to recycle for gold, silver and bronze medals at next year's Olympics. I don't expect it's an economic decision, but it feels good.
Old electronic equipment is the good stuff.
The older it is- the better.
The manufacturers have now created methods to use less gold.
Equipment from the 60s is coveted.
Mainframes and old giant mechanical printers have lots of gold in them.
Telcom equipment, Rf equipment same thing- lots of easily accessible Noble metals.
Today's scrap electronics have much less recovery value but it's still profitable, even in California.
If you follow the correct formulas( developed in the 1800s and not a secret) the waste products from this process are not classified as hazardous.
Yes it takes time for your reactions to complete but, it's not like you have to babysit this stuff.
All the waste is converted into non hazardous elements easily thru cheap effective chemical reactions.
I've said too much already but, if anyone can get ahold of a large quantity of cellphones or better yet older electronics from the past century I'd be glad to help you recover your gold thru environmentally legal methods that aren't a secret but are just not well known.
Hit me up in my profile
Gold is recovered from modern electronic equipment by many people in the USA in a profitable and environmentally clean way.
You don't hear much about it due to the people doing it don't want to advertise thier success.
Modern electronics have much less gold or other valuable metals in them nowadays but wherever you see an electronics recycling event there are modern day gold miners.
The key word here is
" Gold refining"
When was the last time you've seen gold plated USB cables?
Gold plating contacts may have been necessary with analog back in the day, but today's digital equipment is much more reliable thanks to error checking / correcting protocols, and other improvements. Besides, gold contacts wear out faster.
Other metals like the ones you named have an oxidation problem over time.
Gold does not have that problem and contacts will wear thru thier plating by mechanical usage .
Gold does not oxidize in the normal earth atmosphere.
That's why you can see ancient gold in for instance : Egyptian relics that still shine - no oxidation..
It's nearly a perfect electrical conductor.
There are better ( for the pedantic chemists here)
But gold plated connectors are used by industry for reliability
