From the back cover:
You enter the office of the Merchant Guildmaster, heeding the summons of the courier who interrupted your breakfast at the inn this morning. The Guildmaster sits behind a vast desk made of some unknown, exotic wood.
The Guildmaster gazes at each of you in turn. "Thank you for agreeing to this meeting. We have heard many tales of your adventures, of the services you have rendered and the quests you have undertaken on behalf of so many, both lordly and common."
The Guildmaster's eyes drift to one of the maps hanging on the far wall, one that charts the great mountain range to the north. "This guild trades extensively with the mountain dwarves, largely for precious metals of all varieties. Recently, the dwarves lost contact with one of their most valuable mines, Silverhall, which lies in the heart of those mountains."
"Our dwarven friends have dispatched two separate parties to travel to the mines and return with word of what has transpired there. Neither has been heard from since leaving the dwarven holdfast. The dwarves have no entreated us for our assistance, and we intend to provide it."
The Guildmaster reaches into a desk and draws fourth a large leather bag that clinks enticingly when he places it before you. "We ask you to travel to Silverhall and learn what has happened there. If, as I fear, something terrible has befallen the miners, do all that is in your power to find and rescue any that yet live. Do this, and you shall have our gold and our gratitude."
You're not sure which is more valuable, but both could come in handy.