Disclaimer: I’m in the camp of firmly believing that even if a black hole were created it’d be so tiny it’d evaporate in an instant. I do not think the LHC poses any threat to Mankind, Earth or Beyond.
Also, what IS a strangelet? Just as the name implies, it’s very strange. I’ll just post a link here to a site that goes into a bit more detail about what it theoretically is. Here is the path to knowledge