That the Indians had a custom to include deliberate flaws in their blankets - for evil spirits to exit, is an interesting information!

I do not know if you ancient Islamic bead collectors have noticed, but certain "Dhar Verkrun" (eyebeads) are covered with yellow/red "eyes", while a single such cane has reversed colors - red/yellow (from outside in).

I realized this on several occasions and on various such beads. When I had the chance to ask different (!) local "beadwoman" in Mauritania, they told me that only Allah is perfect, never beads. In other words: The single reversed coloured cane was added to the bead on purpose in order to show human imperfection, or, if you will, "god's" perfection!