The full rules proposal for crafting Skorne enchanted items can be found in the Gearbooks II PDF, pp. 136-142.
Auxiliary [Ability/Skill; Sacral Stone Shard]
Vessel: Talisman
Ancestor: see below
Potency: 1 or 2
Shard Points: 2 or 3
Effects: When making a skill roll which has specific additional abilities or skill ranks as its prerequisites, a Skorne wearing a talisman imbued by this sacral stone shard is considered to meet one or two of these prerequisites, as determined by this sacral stone shard’s specifications (see below; this can be noted in the shard’s name as Auxiliary [Iron Will] or Auxiliary [Animal Handling 3]), but still cannot use the specified ability or skill rank granted by this shard for any other purposes. Similarly, this shard cannot be used to provide a skill rank if the wearer of the talisman has to make a roll using the lower of two skills.
This sacral stone shard has a potency of 1, independently of the ability or skill rank required, though the ancestor from whose sacral stone shard the shard has been cleaved must have possessed the prerequisite ability or skill (e.g. if the shard is supposed to grant Great Weapon 3 for the purposes of making a skill roll that has knowledge of Great Weapons 3 as one of its prerequisites, the ancestor in question must have possessed Great Weapon 3 during their lifetime).
Additionally, considering a talisman can hold sacral stone shards with a maximum potency of 2, auxiliary sacral stone shards can also be crafted that satisfy a requirement of two abilities and/or skill ranks, and accordingly have a potency of 2 and a shard point value of 3.
Comments welcome, as usual.