What determines when a mining station stops mining a specific resource?

[secondcircle]

I have a mining station that is mining caslon and krypton, 100% and 41% abundance respectively.
IThis mining station has 1 cargo bay, it says it's cargo capacity is 4800, but I have gotten up at 8k caslon and 3.2k krypton and it may go higher but ships keep taking it off to places.

What determines what the max cargo a mining station can store?
What determines what the max for a specific resource? I noticed my kyrpton stops at 3601, but the caslon keeps going.

I have another station with 3 types of minerals and they all stopped at around 2200.
I'm having trouble making sense of how this works, so it makes it hard to design custom mining stations in a optimal way.

[zgrssd]

The Station has Resource Targets, same as every Spaceport and every Colony.

Naturally Caslon is given a much higher share of the storage space.