Last night I was transferring some cured Fijian live rock from a rubbermaid containter where it has been for a few weeks into a new tank. After handling the rock, I had hair-thin "needles" sticking out of some of my fingers where I had touched the rock. They were very short and thin, translucent, and barely visible except under a light. They were also pretty painful, just as if someone had stuck a tiny needle into my fingertip. After I washed my hands I was able to get them out. Any idea what could have caused this?