Believe it or not… that dialect is French. It is correct for the era of the
video. Historically, that area would have been Walloon, Luxemburgish or
German speaking. Linguistics in Belgium is a complicated matter, especially
close to the borders. That region of Belgium used to belong to Luxembourg,
but Luxemburgish wasn’t spoken everywhere in Luxembourg. In my area, the
use of Luxemburgish in schools was banned in the 1960s.

The sticks they use to blast the vein aren’t even dynamite, it’s just black
powder rolled in newspaper. The work sequence was to drill the holes in the
morning, pack and blast before lunch, have your lunch break on the surface
while the smoke/fumes dissipated, then evacuate the debris to get to the
good stuff.

In this mine, they were just dumping the debris in a tip. Some mines were
actually selling the debris as construction material. Many houses in that
part of Belgium were built using the debris from mining.

The dark violet layer closest to the white/yellow coticule is also a
whetstone… the Belgian blue stone. Only part of that layer contains garnets
tho… so once again, the garnet-less layer is used for construction: windows
ledges, windows surrounds, door surrounds and walkway curbs. The blue stone
is slippery when wet, so you had to be careful stepping off the walkway in
the rain. They have been replaced with concrete over the years.

The quick test to know if the dark side of the coticule is blue stone is
once again to slurry it…  if the slurry is grey/white, you have a cheap
slate back glued to coticule. If it has a purplish hue, it should be the
real deal.