It accompanies in very low quantities aluminum and zinc, so it is extracted only in the mines of aluminum or of zinc, as a byproduct.
However, the abundance of gallium is similar to that of lithium, while gallium is used in smaller amounts, so there is no risk to not have enough gallium in the near future.
On the other hand, all semiconductor devices with gallium also use some indium. Indium is used in even greater quantities in all LCD or OLED displays, to make transparent electrodes.
Indium is an extremely rare element in the entire universe, comparable with gold, so for indium there is a much greater risk that its reserves will become insufficient.
This could be mitigated by extracting such critical elements from the dumped electronic devices, but this is very expensive, because only small amounts of indium are used per device, so very large amounts of garbage would have to be processed in order to extract a sizable amount of it.
(Gallium is a byproduct of aluminum production. We aren't going to run out.)
Unless by “make from something” else you mean extract the element from existing chemical compounds found in Earth, in which case we’re still just using existing deposits on Earth.
The earth's crust is 8% aluminum.
We will have bigger problems before hitting this one.
We will not remain without gallium, but it is impossible to scale up the gallium production to a higher level than provided by the current productions of aluminum and zinc.
So there is a maximum level of gallium that can be used per year and it would not be possible to increase the production of blue and white LEDs and of power transistors above that level.
Fortunately, the amount of gallium used per device is very small, so it is not likely that we will hit that level soon. A much more serious problem is the associated consumption of indium, for which the resources are much less.
The metal isn't going to disappear, but it won't be concentrated enough to be as easily retrievable.
I'm inclined to think we've lost that gold.
In your question you stated the running out as a given fact ("When" we run out, not "if").
If that was what you wanted to say I can't tell you, but that's definitely how it was received and thus you also got the harsh response. Since it reads a lot like doomsday thinking.
(Example: Does that mean when we run out of oxygen there are no more humans?
Why would we run out?)
You still seem to be missing the point.
If you talk about "when we run out", you are presenting yourself as an expert stating "we will run out" and asking about the aftermath.
It would be appropriate, and better received with more leniency, for you to ask whether we would run out.
Of oxygen, because of rising temperatures interacting with rock weathering binding all the oxygen.
Now, that's more of something to worry about at geological time scales, but Earth in fact, is not infinite.
Such predictions have an abysmal historic track record, because we tend to find workarounds both on the supply side (=> previously undiscovered reserves) as well as flexibility on the demand side (using substitutes).
This applies historically for oil, lithium, rare earth metals and basically everything else.
edit: I'm not saying we're never gonna run out of anything-- I'm just saying to not expect sudden, cataclysmic shortages in general, but instead steadily rising prices and a somewhat smoothish transition to alternatives.
But non-sustainable pricing is very different from "cataclysmic collapse", and too many people expect the latter for too many things, which is just not realistic in my view (and historical precendent makes a strong case against that assumption, too).
A society where water prices gradually increases to "reverse-osmosis only" (instead of "pump-from-the-ground-everywhere") levels is very different from a society where water suddenly runs out.
That's a classic example of the "preparedness paradox" [1]. When no one raises the alarm in time or it is being ignored, resources can go (effectively) exhausted before alternatives can be found, or countries either need to pay extraordinary amounts of money or go to war outright - this has happened in the past with guano [2], which was used for fertilizer and gunpowder production for well over a century until the Haber-Bosch ammonia process was developed at the start of the 20th century.
And we're actually seeing a repeat of that as well happening right now. Economists and scientists have sounded the alarm for decades that oil and gas are finite resources and that geopolitical tensions may impact everyone... no one gave too much of a fuck because one could always "drill baby drill", and now look where we are - Iran has blasted about 20% of Qatar's LNG capacity alone to pieces and blocked off the Strait of Hormuz, sending oil prices skyrocketing.
Yes we can run out of oil, but nobody really knows if or even when that will happen. Right now I'm guessing we won't run out because wind and solar is so much cheaper for most purposes everyone is shifting anyway - this will take decades to play out.
If you had made predictions/scenarios in 1850 based on Guano deposits running out within a decade or two, you would have mispredicted completely, because a lot of the industry just transitioned to sodium nitrate (before synthetic fertilisers took over). Nowadays media landscape would've gladly made such doom-and-gloom predictions for global agriculture back then.
I completely agree that quickly depleting reserves often indicate non-sustainable pricing for ressources (which is obviously bad long term), but that is very different from sudden collapse.
yyy! if we're going to wander off-topic :-) then I should mention elevators, water pumps, fire suppression including fire truck ladders and more! :-)