One object to start a conversation
A familiar thing can lead to a story without turning the evening into a presentation.
Pick something with a connection
A postcard, an old sketch or a small object from a trip can give a conversation a starting point. Choose one you actually want to talk about, rather than the most impressive item in the room. Keep the explanation short enough for someone else to respond.
Follow their interest
If a guest notices a different detail, let the story move in that direction. There is no need to explain the entire collection. Put the object away when the conversation has moved on, leaving the table available for whatever happens next.