Gold dust? It can happen but it's not a regular thing because God does things to glorify himself and further his Kingdom, not to wow audiences. I've experienced silver dust and I was pretty skeptical about the whole thing. I was talking to a Christian friend about moving interstate and how I'd only know God over there. While he was talking, silver dust appeared around his eyes and on the sides of his face. I didn't believe it at first but I stopped my friend and talked to him about the dust. He said he'd had this happen before and told me that God was communicating something to me.
I asked him what silver dust meant. He said Truth - to trust God to his promises (that God would go before me and never leave me as I took the step of faith he had asked of me). I later researched it to confirm what he said, and it was true. He wasn't trying to mislead me. I was blown away by such a sign. It was a small miracle from God! Don't worry, he's not a false teacher or anything - he told me to check what he said with God's Word and ask the Holy Spirit for guidance. I'm very thankful for the experience, and while I don't look for signs, I'm a little less skeptical of such things being possible (and from God).
