Thanks for the feed back. I am also curious has this compares to my standard issue steel amour.
It doesn't. Artifacts are as good as masterworks of the same material, except that they give an additional bonus to the user's combat skill (for armor, that probably means Armor User, for shields it's Shield User, and for weapons it's the appropriate weapon skill). Since Armor User doesn't actually directly do anything for combat, artifact armors aren't significantly better than a masterwork of the same material. Materwork leather armor isn't anywhere near as good as even no-quality steel armor, so artifact leather armor doesn't compare to steel armor, either.
I'd give you the quote from Toady on how artifacts worked, but unfortunately the wiki is down again and I don't know exactly where on the forums it is.
I think masterwork leather armor is equal to base quality iron, so I'm not sure what artifact quality is equal to.
MW leather
used to be equal to base-quality iron, but with the materials rework that came with 31.01, it is generally agreed to not be anymore. In version 40d and earlier, materials had a simple percentage effectiveness, with iron as the baseline 100%, and masterwork-quality items doubled that effectiveness, so double-effectiveness Masterwork on 50% effectiveness Leather was equal to iron. Now, however, that is no longer the case, and materials' effectiveness is no longer so simple.