When it comes to Michigan copper, I personally look for 3 things: clear sharp crystals, good patina, and an attractive overall from.  This self-standing piece checks all three boxes, with numerous crystals and crystal faces visible throughout, and the left branch being a cluster of large, elongated crystals with very clear form.  The overall shape of the piece is quite sculptural as well, and the size and its visual balance make for a particularly nice display.