Hi there! I discovered your game through Mr Fruit's Gaming Channel, and I think I've developed a small addiction at this point. :P
One of the more annoying bugs I've discovered is that, sometimes, a sale is made that doesn't factor in the metal used - it'll simply say the weapon type with no metal mentioned and then a measly price. I've noticed it happening more since getting to iron (though that may just be because it's more noticeable), and it seems to be happening more often with swords and greatswords - I think it has happened with every single iron greatsword I've made (though that may simply be a coincidence). I am playing version Alpha 0.0.731.
Anyway, love the game! It's a great little pearl, and I can see it becoming quite amazing! :D
UPDATE: All right, so I've discovered that the bug already occurs at construction - it will sometimes merely say, for instance, that a greatsword has been constructed rather than an adelite greatsword. In that case I have found that I can simply take it apart and try again until it works (though it may require a few attempts). At one point I even experienced that a tin greatsword I was making turned into an iron greatsword upon construction (the blade was still identifiable as tin, but it sold for the price of an iron greatsword - perhaps incidentally the previous iron greatsword I had made only sold as a greatsword, which was the reason I was forced to make a tin one). Looking back, I can see that it was happening all the way back with copper, but the price difference was so much smaller I didn't notice. The greatsword was always the main culprit, though.
UPDATE: Regarding swords and greatswords, combining the grip and handle before attaching the blade seems to avoid the issue. I have had no cases of "metal-less" weapons being constructed today. (Though I had one greatsword that freaked out when I put it together, causing a slight mess in my workshop and ending up with a crooked handle. The customer who got it was still satisfied, though.)