Stone is split by hand until it rings true, and you reserve a slate riving day in the Belgian Ardennes to hear it

Seven hours around the splitting bench

You start at 09:00 at the quarry rim, where the faces are pointed out and the reason one seam splits and the seam beside it does not gets explained in about ten minutes, standing in the wind. The rest of the morning is under cover. Blocks come off the pile, get sawn down to length, and then the riving starts: a broad chisel, a wooden mallet, and a sound that tells the man whether the stone is going to open true or not. You try it yourself after the midday plate, on stone nobody expects you to save, and most people need thirty attempts before one comes off clean. It ends at 16:00 with your own pieces, in whatever state you made them.

Dust, damp, and staying on your feet

Little walking, plenty of standing: about five hours upright on a concrete floor, broken by two seated stops. The shed is open at one end and unheated, so in November it is properly cold and in August it is pleasant. Stone dust is in the air whenever sawing is going on and you are given a mask for that part, but anyone with a chest condition should weigh that honestly before booking rather than after arriving. Riving itself asks for a steady arm rather than a strong one, and people who expected to be useless at it often are not. Closed shoes with a stiff sole are required, and the works turns away open sandals at the gate, which is not negotiable.

What the $168 stops short of

The figure holds seven hours with the men who do the work, the stone you spoil while learning, the mask and the eye protection, a hot plate of food at midday, and the pieces you carry away. It does not hold your travel into the Ardennes, a bed, anything you buy on the way home, or cover of any kind against injury, which this office does not sell and will not pretend to arrange. Because the day needs eight, the figure does not drop when twelve of you come. If the eighth booking never appears, the day moves and nothing has been taken from you, because the works bills you directly and only after you have been.

Awkward things people ask about this day

Can children do the riving?

Not under twelve, and that is the works' rule rather than ours. Below that age the tools are the wrong size and the floor is the wrong place to stand while other people are swinging a mallet. Twelve to sixteen is fine alongside an adult who stays within arm's reach for the whole afternoon. We would rather tell you no now than have you drive two hours and be turned round at the gate.

Is the quarry still worked?

Parts of it, at a fraction of the old scale, and what you walk into is a working floor rather than a museum floor. That means the order of the day bends around whatever the men are actually doing that week, and once or twice a year it means the whole thing moves because an order has to go out on time. You are told as soon as they know, not on the morning itself.

Do we keep the slates we split?

Yes, and you should expect them uneven, because a first day at the bench produces uneven slate. Two or three pieces each is normal, roughly the size of a hardback book and heavier than they look, so leave room in the car. If you break every one you attempt, the men will hand you something they split themselves rather than let you leave with nothing, which happens more often than anyone admits.