A young girl slides amber (or precious stone) beads along a necklace (possibly belonging to her grandmother or found in an old house or bestowed upon her?) to travel to different periods in her own life and maybe throughout history, with a specific goal. She sees herself as a young woman, a grandmother. Her siblings are involved somehow, particularly a younger brother. At some point a knife or bloody knife portends something about how her younger brother is doing back in the present day (much like in many fairy tales). Her name was simple and classic like Jane or Anna or Annie. This book must have been published pre-1987, when my school librarian suggested it to me. It seemed already old at the time (which may just have been kid perception) so could possibly have a publish date anywhere from 1940s through early 80s.
It was a chapter book. Though it may have had a few line drawing illustrations throughout the text, it was not a picture book.