Might have lost my gold card or not sure I even got one. Is it sufficient enough to provide the Marriott # at check-in?
Yes, the number is sufficient. You will rarely, if ever, need your physical card.
If you get challenged for whatever reason (like o0o0o0o0o0o...points! had said would be a real stretch), you could show them the Marriott App if you have it loaded onto your cell phone.
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