It's a fantasy role-playing game.

DM: You are Percival de Rolo, a human gunslinger . You are the member of the famous group of adventurers. Previously, Percy goes with Keyleth and Tiberius to look for ammunition supplies. Though black powder is not a commonly-sold commodity in Vasselheim, Percy manages to find one eccentric older man who sells it.
DM: Yeah, you walk to the distant brick building. The bricks themselves are made of a hardened, grayish clay material that's been made in the basic construction of this. The roof itself is a solid slab of stone. There is no pretty or elegant aspect of its construction. It's merely built here for purpose. The door is partially ajar, and as you peek in you can see there is a very active forge. There is a heat emanating from the interior, and you can see there is a man who is currently hammering something away at what looks like an anvil set outside in front of it. (metal clanging) "Yes?"
Player: Mr. Samson?
DM: "Yes?"
Player: The strange fellow down the road sent me to you. He said you might have some ore?
DM: (heavy sigh) The head sinks into the shoulders with a sigh. "All right. If you dealt with that crazy old coot, at the very least I can offer you a brief conversation. Hold on just a second!" (grunts) And you see he takes this visor off the front of his face and sets it down and removes these big leather gloves and this leather apron of sorts and puts it to the side, and he wipes his brow as he steps over. And you can see him now. He's a man in his late twenties. Muscle-bound, a little thick around the waist, barrel-chested. A little bit of scruff on his chin, but nothing beyond not having time for upkeep and focused on his work. He steps up. "So what did the old coot tell you, anyway?"
Player: He said you might have some raw ore for sale that I might purchase. You'll excuse me if I don't come in; I'm covered in explosive powder.
DM: "No, please. Stay there. For the love of Kord, stay on that doorstep. Do not step into my abode, please."
Player: Of course.
DM: "Please."
Player: No. Yes.
DM: "Please. All right. What ore are you interested in?"
Player: Just some iron ore. Actually, I have a little invention which sends projectiles at great speed.
DM: "That sounds fascinating. I have ore for sale. Raw ore-- would you like ingots? I prepare ingots. They're a little more expensive, but they're proper and ready for any sort of use as blacksmithing materials."
Player: Ingots would be preferable, yes.
DM: "All right, how many are you looking for? Five, ten, 20?"
Player: What could you give me for approximately a thousand gold's worth?
DM: He gives you an arched eyebrow in surprise. "I mean, I only have about 200 pounds of iron ingots at the ready."
Player: I certainly can't carry that much with me right now. Let's say about a hundred pounds' worth?
DM: "A hundred pounds of iron ingots. I could sell it to you. Let's set the price at about 400 gold pieces."
