How much is a Artifact.

[Storminator]

The Hammer is a pretty reasonable weapon for a 20th level character to tote around. It's +5 enhancement, the damage (4d6) is about equivalent to 2 of the +1 enhancements like Flaming or Frost, the thunderclap on throwing has a terrible save DC, but a nice effect, so that's probably a +1 equivalent, the giant killing isn't nearly as good a Vorpal - it has a pretty easy save and limited use - but it's probably worth a +2 (assuming there's giants in the campaign). Letting the enhancements of the belt and gauntlets stack is about the same as making the enhancements on the gauntlets untyped, which would be a multiple of 2.5 to the cost of 4000 gp.

That makes the Hammer about a +10 item + 6000 gp. Total 206,000 gp.

I'm pretty sure you could easily make a nastier weapon for that kind of cash (+3 holy, keen, frost, shock, spellstoring, vicious bastard sword?)

PS

 

[Storminator]

In fact, absent the DM putting an artifact into the campaign on purpose, artifacts should never come up as a part of the game.

That's one way to go. Another way to look at is that by Epic tier everyone should have had an artifact at least once. IMC, the PCs had and lost both the Eye and Hand of Vecna, one of them is wearing a permanent uncontrolled Contact Other Plane effect, another has a dragonmark that is growing in size and power each adventure. As soon as the other players come up with ideas they'll get artifacts too.

PS