Final Fantasy 15 – What Does Servicing the Regalia Do?

From this post the dial represents:

How long time has passed since you last rested. If it's 0 then that means you spent less than 24 hours game time in the world from your last rest.

I also believe that the two yellow colors indicate the sunrise and sunset (the bottom yellow/orange color is the sunset, the dark blue afterwards is night, the top brighter yellow is the sun rise, the light blue after it is day).

I have not found any means to obtain bulk lots of ore, so far in my gameplay (Chapter 6 30h+).

The best way to gather ores is to speak to a local restaurant proprietor, who will mark the local procurement points on your map. The pickaxe icons are the ones to keep an eye out for.

Then you'll need to visit these spots and collect the ore. The procurement spots do seem to regenerate after a time. So you can 'farm' these ore nodes by revisiting them once they've regenerated. The icon will change from grey back to yellow.

Unfortunately I haven't been paying enough attention to notice if certain ores spawn in the same spot each time, so that you can gather multiples of the same. I know the treasure spots do contain the same items every time though, so the ores may well do as well.