If you want it to rust 100 %
The acceptable limit is usually 0.3mg/Litre
In order for you to keep your iron pot from rusting, you will need to keep it away from any water or moisture. I have also found that coating the iron, such as a seal or paint will dramatically limit the amount of rusting.
Its the moisture which causes rusting of iron
iron, moisture and air
Rusting is caused due to exposture of iron to moisture. When iron articles are painted, it is not exposed to the atomospheric moisture. This is how paint stops rusting
iron, moisture and air
Coating prevent the iron from contacting air and moisture. So it prevents iron from rusting.
iron rusts faster in presence of moisture and air.
Because of the moisture.
The reactivity of iron is quite high, as it reacts by coming into contact with moisture in the air.
Depends what you call "too much". The current acceptable limit is now 3ppm, but I have seen people drinking with over 8 ppm and not being bothered by it.
It easily becomes rusty.