Hmm, so that's where I left my ball peen hammer!
I am leaning more with the pyrite or something like it explanation since its only 0.5 cm tall,
Although I give props to Arken and Hugo, Arken presented it as a living creature (nothing wrong with that BTW) and the OP is presenting it from a
scientific angle with listed sources.
Think we can handle two different thread viewpoints on the subject but in the end that is for the mods to decide.