The Dragon Armor that the dwarf king Freyedies makes for you is a very strong armor for this part of the game, especially if you then add blessings or enchantments to it afterward. The problem is, there are only two chunks of Dragon Ore in the mine. Each will get you one suit of Dragon Armor. A third suit is in the king's private treasure room in the chest.

To get as many Dragon Armors as you want, give the ore to the dwarf king, and let him make the armor (leave the room, go back to the first intersection in the mine tunnels, and then go back. He should be done by then). Then, have the person who gave him the ore talk to the king, and get the armor. Then, get your thief to steal the ore back from the king. Note: This is difficult. You will need a steal skill of at least level 5, but the higher the better. Then, give the ore back to the king, and he'll make you another suit of armor. Do this as many times as you want. The Dragon Armor is a good item to use for the 2nd level infinite money trick. You can use this trick on the dwarf workers. But once you sell them about 4 or so armors, they will no longer buy them from you. I used 4.