What is a proper noun of rum?

There isn't a single "proper noun" for rum in the same way there is for a specific brand of whiskey or wine.

However, rum often has proper nouns associated with it based on its origin or specific type.

Here are some examples:

* Brands: Bacardi, Captain Morgan, Mount Gay, Appleton Estate, Havana Club

* Regions: Jamaican Rum, Puerto Rican Rum, Cuban Rum, Martinique Rum

* Types: Dark Rum, White Rum, Spiced Rum, Aged Rum, Demerara Rum

So, while "rum" itself is a common noun, you can find many proper nouns associated with specific brands, regions, or types of rum.