This has gotten my interest. Would an Artisan weaponsmith work out as a character? Particularly a Gunsmith of some kind. They would be one of the Artisans in The Duke's Cardinal city so I'd need some canon details regarding life there before I can make up their background. Because they would either be designing for private merchants or for the military depending on the lifestyle of that place.

I was also thinking of having their Mineral weapon as an ornate scoped rifle with a gem that acts as a specialized scope which will only zoom in properly if you're aiming to disable instead of kill (such as hitting the arms or legs of a target instead of torso or head). Otherwise the scope becomes wonky until you aim at something less-likely to be fatal. There is also a high chance of misfires or shots going way off target if you try to shoot with the intent to kill. But if you aim for a disabling shot it lands with near-pinpoint accuracy and a well-adjusted caliber to make sure the bullet does not fall short. I could probably call it something like the "The Negotiator" or "The Pacifier" :lol