How can a halibut hook be sacred? Pretty much everything from the bygone era is now "sacred" because it represents a way of life that was abandoned, or extinguished, depending on how you look at it.

We (non-Indians) tend to look at old stuff as antiques or junk. The antiques we sell, and the junk we throw away. Some of the junk is designated as antique to justify charging tourists big money for it, but antiques and junk have one thing in common: they are for sale. Even things that came from old churches, including icons, stained glass, communion chalices, etc. are for sale. We regard them as symbolic, but not holy or sacred, and have no problem with selling or trading them.

It's a different story for Indian people. They thought the way they lived, the things they did, the fish they caught, were designated for them and given to them by their creator. That halibut hook was probably not sacred when it was used to catch halibut. The owner probably traded to a white man for something like a knife or ammunition. But it's a sacred artifact now because it represents a way of life past the living memory of most people. I don't think they would have asked for it back if the museum treated it with a little respect, but selling it is pretty crass behavior. They should be forced to send it back where it belongs.