Salt Wife

"A man had his rock wife, his true bride, ironborn like himself, but he had his salt wives too, women captured on raids."
- A Clash of Kings

A salt wife was a wife of an Ironborn man who was not herself of Ironborn descent, generally captured on a raid. She would be of a similar class to thralls, and any sons born to her would be considered Ironborn; fully able to inherit his father's lands, provided there was no living son born of a rock wife. Salt wives were not whores or slaves, but rather a type of concubine.

While a man could have as many salt wives as he'd like, he would only have one rock wife.