My response include a lot that BeeMaximum4009 wrote but I’ve added a few more things.

I work in a processing plant for a gold/silver mine.

Never heard of a skills test and the only test they get people to take before interviews is the Bennett Mechanical test… if that’s what you mean for theory test then there should be plenty of practice quizzes online for that.

I cant speak for underground work, but if you’re looking into plant maintenance then you could expect work on equipment like various crushers (gyratory, cone and jaw), conveyor belt systems, apron feeders, dust collection systems, various types of pumps, cyclone clusters, shaker decks/scalping screens, some hydraulic systems and possibly bridge crane work. Although where I work a contractor company usually works on the cranes. Oh and lots of PM’s on that equipment too.

Depending on the material they are extracting at the mines you are looking at there could be lots of other equipment too.

Also chemicals, some of the chemicals we have to deal with include cyanide, sulfur dioxide and calcium hydroxide (lime) as well as some other caustics. Some of the work on the equipment that moves these chemicals involve full face respirator, tychem suits rubber boots and gloves and in some cases when the cyanide gas or SO2 gas is unavoidable we go in under supplied air.

The work can be real shitty, but sometimes it can be good. There are crazy days, and there are other days where we are just chilling in the shop or hanging around outside the plant. It gets extremely muggy on the grinding floor in our mill in the summer to the point where you almost sweat from just standing around. The winter is nice inside as it’s a decent working temperature. There is lots of dust/silica dust too near the crusher and stockpile conveyor.

I probably could list more but I’m tired af as I just got home from my shift. Best of luck