ToME: the Tales of Maj'Eyal

Is it just me, or does the value of the gems one can extract from metal items as an alchemist always exceed the value of the original item (with the possible exception of very high-ranking ego items)? If so, an alchemist will always get considerably more money out of selling items than any other class, because they can turn them into gems first.

I guess it makes a sort of sense for an alchemist to be inherently wealthier than other character types (metal into gems being like lead into gold), but is this intended game design?

Yes and yes.

Any class can pick up the Stone Alchemy tree, with a fair amount of luck and skill. But money isn't incredibly important for much of the game, although there is a good reason to be wealthy near the end of the story.

Also remember that an Alchemist has to convert a certain percentage of his gems into ammo, which cuts into his profits. He also -- maybe more importantly -- has to get gear and runes for his golem to use it to full effectiveness, which gives him more need for early-game money than other classes. In my experience, when I play an Alchemist, I make more money, but also tend to spend more getting my Golem kitted out.