Would it need to be agitated constantly? Like one of the comments said I think once it hit water it would harden, and it would be expensive to agitate the whole process. I don't understand it that well though. Why does it only pick up gold if you know? If they used another variation of the starch fragment would it stick to PT or other metals? That's random that it only picks gold. How hard is it to get the bromine out or is that not a problem? Sorry for so many questions. Thanks for posting cool article.