its lint, i have identical tips. i had to actually brake some hairs to take it out. and guess what it was? hair from my dog.
updated by @andres2: 07/16/15 10:12:28AM
the shampoos from dreadlockshampoo.com, seem to get most link out..if u scrub the whole dread well (bar)
i was amazed they got out lint that was in there for years