The same as lead (Lead(II) iodide is golden), Pyrite (well, with a strong enough magnet and/or enough knowledge, you might be able to see its paramagnetism - but not in small enough quantities), brass and bronze, tungsten, …
This does not help if you have a bar whith a thin gold coating on it.
That’s the problem with tungsten: It has almost the same (and I mean it: it’s really, really close) density as gold. You can read up on a lot of cases where tungsten bars where layered with a thin gold coat or gold bars filled with tungsten to trick other people, sometimes even including banks and treasuries (although not anymore, since this method was discovered).
… And that’s the problem. You take a look at it from now, where you know it has value. Like… current currency. You even stated that the dollar would lose its worth because the “assigned” value is gone, but the gold would keep its value (or at least some of it) because people now know that it has value - well, we also know now that money has value; why does it lose it then but gold doesn’t?
A gold cube messuring 8’869.743 m³ would have a weight of 171’363,43476 metric tons. Assuming a population of, let’s say… 8 billion humans and 0.1% survivors, there would be 21,4 kg of now useless gold for anyone (well, more for raiders and less for people bunkering down, i guess). Are you sure this is what you call “rare”?
The other less rare things you named can all be used if you come into a place where you need to.
If the cataclysm just struck and there are living (haha, well, that’s debatable) monsters just roam the street I wouldn’t weigh myself down by carring gold…