I have gathered some salt in the Death Valley and for the fun of it I would like to clean it and make it edible. The process I plan to follow is simple:
Dissolve the salt in water.
Boil water for 30 min to kill bacteria.
Filter water to remove foreign particles.
Evaporate water to get clean salt.
At step 3, I'm planning to buy paper filters with pores of 3 µm to filter fine particles. Is it sufficient for the purpose of human consumption?
I'm mostly wondering if there is a key pore size threshold beyond which it is significantly less useful to filter, or if it's just a matter of degree, the smaller the better at an consistent size/benefit ratio.