There appears to be a number of times that bones or an excess of bones appears in the Magnus Archives, included here are extremely sharp bodies that may be caused by bone.
When Mary Kaey passed her copy of Ex Altiora through shadows a number of small animal bones fell from the pages.
The pipes that the piper plays is made of scrimshaw bone.
Ivo Lensik's father was a diagnosed schizophrenic. He told his son that someone was following him, trying to stop his research and that Ivo would know him when they met because "all the bones are in his hand". Agnes Montague hung herself when the old tree at Raymond's house was uprooted, she had a severed human hand with her.
Jared Hopworth found a book entitled The Boneturner's Tale, he seems to have been able to learn how to absorb or remove bones from people and animals without killing them. He appeared to have added more bones to himself, although the limits of this ability or extent or method of this power remain to be seen.
Michael seems to be some sort of entity or creature that looks like a man, except when viewed through distorted glass or reflections. When seen this way, he seems to have long limbs and giant hands. It's possible that he is a boneturner, similar to Jared Hopworth, as he was able to reach into Sasha and remove one of the silver worms.
The seven students who learnt anatomy from Lionel Elliot were able to change their bone's shape with an unsettling crunching noise.
The esoteric musical group whose audience kills itself is named Grifter's Bone.