Memento
Part of speech: noun
Definition: A keepsake; an object kept as a reminder of a place or event.
Example sentence: Recording a scene with paint rather than film sinks you more deeply into your surroundings. You have to look a little harder and a little longer. And you end up with a memento.
Souvenir
Part of speech: noun
Definition: An item of sentimental value, to remember an event or location.
Example sentence: The Masters is not greedy. You wanna buy a Masters souvenir logo shirt? Sure, let's go over to the nearest Ralph Lauren boutique. Oops, you can only purchase Masters memorabilia at the Masters, this one week of the year.