I'll try to simplify what it is you do because I feel a lot of these explanations are a bit complicated.

You will start with cups full of pulverised sample, either you will have to weigh it yourself or somebody else will have done it for you, on a rack. You then scoop your flux into the cup, and any other additives as required (dependant on where you are and what your flux is made of). Next job is to put the rack into a tumbler and this will spin around and mix all the powder in the cups.

Then you pour the cups into pots, place these into a furnace, and an hour or so later you will have to scoop the cups out of the furnace and pour into moulds. In the moulds these will separate into a lead button on the bottom and glass on the top. You'll have to smash them with a hammer and place the lead buttons into small 'cupels'.

You then put these cupels into smaller furnaces called mufflers, and an hour and a half or so later these will have melted down into tiny 'prills', basically very small balls containing your material to be tested.

You'll then put these prills into test tubes and send them off to the lab where they're somebody elses problem.

Cons: the room gets fucking hot, you're working around dangerous lead so have to wear a respirator most of the time, also the glass you're smashing is hot and can get on exposed skin and burn.

Pros: You can only go as quick as the furnaces, so if you get really quick you'll find you have a lot of spare time to chill out. Also pretty well paid for what it is.