If anyone does have some other info on these things, please pipe in.
But for now, I just grabbed 8 runics to do a mini test with. (2 DC, 2 SH, 1 Bronze, Gold, Aggy, Verite)
They do appear to have the same runic bonus's as runic smith hammers. But one HUGE drawback. With 100 Carpentry, the woodworkers bench, and a +26 exceptional bonus tali...I still only have a 45% chance of crafting the sword exceptionally.
@Canuker - Used one of the DC and SH mallets to test armor (Still terrible exceptional chance I should add) and they do not have any special bonus like the sami armor.
@Gimlet - Since there aren't any special recipes, I'm not seeing a sure fire way to produce relics other than using the higher end mallets. I did get some from the gold-verite runics in various quantities. I also don't have any colored stone to work with, I'm sure that could help with relics if the same material modifiers are in place for stone items.
First stone war sword I made with a Verite mallet did look like this:
48 Lower Defence
90 Mana Leech
40 Lower Attack
40 Fireball
55 Damage Increase
So, maybe that's what I should use them on. Though, you might be able to get some pretty crazy armor pieces too..