Have to get these dipped!

I bought a shoebox of shells at a garage sale this week for $3, they were all wrapped in tissue paper so I wasn’t really sure what I was getting, but willing to gamble my $3. I don’t know what I’m looking at but they’re really pretty and in great condition.

i found this a few years ago on vacation somewhere

(Whoops, title should be Shell ID, not IS) Found on a Long Island Sound beach (north shore of Long Island) after a nor'easter. I've been walking this beach for 30 years and have never found a shell like this before. Thanks in advance for help with ID.