If you're collecting them from Michigan lakes, they likely are not. A ban was put in place long ago because divers were decimating the populations hunting for freshwater pearls. they were also using the shells from clams that work good for pearls, but they would take fragments of the shells and insert them in the types of clams that were.
Additionally, you would likely have a lot of trouble keeping them alive long term because they are filter feeders and most home aquariums do not have enough food material in the waters to sustain them long term.