I have some good description info for you as well as a question / warning to others.
Tested at level 19 (doubt it scales):
Eternal Artefact +
Helm = 2 Finesse, 1 Huntsman
Neck = 10% Fire Res, 2% Crit, 5% Dodging
Ring = 1 Scoundrel, 10% Poison Res
Chest = 10% Air Res
Gloves = 2 Con, 10% Earth Res
Belt = 1 Strength, 1 Warfare
Boots = 1 Thievery, +0.1 Movement
Pants = 10% Air, 1 Polymorph
Weapon (non-Staff, non-Wand) = +Air Damage
All items saw a VERY small increase in their physical armor (or magic armor for jewelry). Usually it was around 5%.
Warning! There are two types of Eternal Artefacts. They have different images, one has a value of 700g and a weight of 1.0. The other has a value of 350g and a weight of 0.4
The second one doesn't work for any of these, but it is showing up in the materials tab. I tried to combine them and such but I expect it's a bug on Larian's side. If it's not a bug and someone figures it out I would love to know, I have a lot!
