Hello Riverwind and Welcome!
That is an interesting sample, have you tried chipping a small out of the way section of the goldish colored material to see if it just fractures or if it absorbs the blow (bends)? that would be a start at identifying it. If it cracks then it is likely Mica, if it bends, flows, is malleable then it could be something special. Good Luck and thank you for sharing................63bkpkr