I'm sentimental too, so I don't think I could sell it (unless it went to pay for something else sentimental, like a wedding). If it wasn't my style, I think I'd save the stone and have it put in a new setting that suited either my style or a future daughter-in-law's style (for example, giving the stone to my son for his bride).

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Depends on who it is from. If it is from a beloved family member, I'd keep it. Maybe have it made into another form of jewelry for my kids. But if it was from a family member I didn't care for, I'd sell it.