Dragaus: What Keeps the Lights on in Bharaggendir

I've spoken to many a lad about what life is like down in the mines beneath the Muiraces. They always tell me how terrible the work is and how many a dwarf die in a year's time just to get their grubby hands on Dragaus. Those damnable crystals are what's tearing the city asunder if ye ask me. Ever since the discovery of the things about a hundred years ago, every artificer in the city has to have them. Instead of good, old-fashioned oil or what have ya, but no, they'd rather use these things that cost a cart full of heads instead of what we already got. Makes no sense to me.
The only thing I can figure is that magic is coming back hard and strong and it shows no signs of stopping. See, these crystals are dug up from the deepest parts of the Muiraces, the most dangerous part of the country. It's infested with the undead, mutated goblinoids, and strange arcane phenomena. The miners are more akin to warriors and Bravesouls at this point than anythin' else. Daffy bastards speak on how they made away with wagons of Dragaus after felling many a risen soldier. "The best way to make heads in Bharak-dur" my arse. Can't tell ya how many a sorry lass comes into the tavern on 3rd and Park sobbing into their ale about their dead father, brother, or lover. Makes me sick to think that the Aristocrats encourage this sort of shite. I'll stick to the old plain-and-simple smithy work I've done since I was a lad. I must admit that it has crossed my mind what exactly lay down in the depths. Probably some sort of eldritch horror waiting to be unearthed to consume the lot of us, or so I hear a doomsayer speak.

Properties

Material Characteristics

Chalky crystals that vary in color from pink, gray, blue, and red. There's rumored to be a black Dragaus crystal as well.

Physical & Chemical Properties

The crystals possess the natural ability to store and amplify the power of magics conjured into or through them. They reflect bright and brilliant colors when magic is stored inside or is passing through.

Compounds

The crystals are used in just about anything an artificer or inventor could think to fit them into. Including but not limited to vehicles, weapons, lights, and even clothing.

Geology & Geography

Dragaus is located underneath the Muiraces mountain range.

Life & Expiration

These crystals take a lot of use before eventually cracking. A smaller crystal could handle a year's worth of moderate use while larger ones could handle up to a decade's use.

Odor

Earthy, like limestone

Color

Pink, gray, blue, red, and possibly black