“A dark liquid that catches fire so very easily.” This is a good description of the alcohol called 151-proof Rum. It is also known as over proofed rum, because of its high alcohol by volume content. It contains 75.5% alcohol compared to the usual 35-40% found in the regular alcoholic beverages. Ever seen a bartender dazzle customers with a cocktail or a shot that is ignited and served with the “flame on?” Chances are that the drink uses the 151-proof rum as a float, meaning, the drink is made and then topped off with this Rum which is then set on fire. This Rum is also used to make punches and over proofed cocktails.
There aren't too many brands that manufacture and sell the 151-proof Rum. Bacardi is one of the best known brands. Other well known brands manufacturing this particular beverage are Appleton Estate 151 proof Jamaican Rum, the Don Q 151 Rum, and the Jack Iron Strong Caribbean Rum. The 151-proof's high alcohol content makes it a very potent beverage. There are quite a few countries where this alcohol is either banned or simply not available. Some of the good pieces of advice when it comes to the 151-proof: do not drink it straight and always be careful when making flammable drinks.
The over proofed rums usually come from the West Indies or Guyana. The 151-proof Rum is one of the few drinks that usually comes in flame retardant bottles like those of Bacardi. The drink can add a kick to any Rum based cocktail – the most famous being the Caribou Lou. Take 1 part Malibu Coconut Rum and mix in with 1.5 parts of the Rum and 5 parts of pineapple juice. Make sure you don't have too many of the Caribou Lou's and drink responsibly. Other famous shooters and cocktails that use the 151-proof are B-51s, the Fireball, the Original Mojo, the “happy” Mojito, the Sex in a Shot Glass, and the Shark-bite.