The smoking gun is Aaron O'Connell's research. You can see a Ted talk called "Making Sense of a Visible Quantum Object" quite easily online. You can totally isolate a tiny piece of metal--huge from a supposedly quantum scale point of view though--and when you do, you see it vibrating and not-vibrating simulateously. By definition your mind has not put it into coherence, since it's isolated, in a near vacuum near absolute zero. And it's HUGE, millions of times bigger than a quantum such as an electron or proton.