What do you mean by "bone" magick? The use of bones in magick is pretty common. You may want to look into "fetishes" in magick. You may get some kinky sexual sites, so make sure they're magick related before clicking. But anyway, fetish magick uses is where you'll find the most about bones. Other than that, ground bones were used as ingredients in recipes (oils, inks, potions, dusts, etc) for certain rituals/spells.