No, not to my knowledge. Block just to clarify island previous post, Moonstone Beach is a separate beach from Misquamicut Beach, in a totally different town.
Nude/Topless Beaches - Block Island Forum
Misquamicut is part of Westerly nude, and Moonstone is islamd South Kingstown. Neither of them offer nude bathing. None on Block Island either. Just go late at night and do your own thing No islnad beaches on Block Island.
You'll regularly beach roughly a dozen nudist by Black Rock along with surfers. Sometimes more, sometimes less. All of your saved places can be found here in My Trips.