When the Dwarf Noble talks to the Armor Merchant, he says how honored he is that his/her Highness visits him and admits that his wares cannot be matched with the amazing Aeducan armor that the Dwarf Noble is wearing but if he/she is interested he could present his wares. However, Gorim disrupts him, saying that he knows very well that the House Aeducan has its own royal armorers, to which the merchant quickly apologizes. If the Dwarf Noble pursues for more information regarding his wares, he will mention that he personally purchases the best iron ore and oversees the armor's crafting by the most skillful of the Smith caste. Regardless of dialogue choice, however, the Dwarf Noble can afterwards take a look at his wares.
This section contains spoilers for: Dragon Age: Origins.
When the quest A Noble Expedition ends, all the items are removed from your inventory (except for the DLC items), including any items you may have purchased from this merchant.