As a judge of rum, I am often asked how do you compare all of the different types of rum? Actually you don't. Rum is broken up into categories so you can compare them to members of like attributes. For instance you won't generally compare a white mixing rum to an aged dark rum, they are two completely different animals. Therefore we break rum into classifications.White Rums: These are usually continuous distilled light rums that are not aged. There are some exceptions, a few are aged and filtered to remove the color gotten from the barrels. Most of these are "mixing rums" in that they generally do not have much flavor to allow them to be sipped.. Like all generalizations there are exceptions to the rule, some are made in "pot stills", especially ones coming from smaller low volume distilleries and some have been aged enough to be flavorful.
Gold or Amber Rums: Sometimes referred to as "anejo" the are rums that have been aged in wooden casks for a relatively short period of time, usually 2 to 5 years. They tend to have a golden or amber color. These can be quite a bit smoother when compared to the white unaged rums and they have subtle flavors that emanate from the reaction of the alcohol with the wood. These rums are also usually the product of a continuous distilling process. They tend to be a lower viscosity than the rums that come from the pot stills. One other thing to keep in mind, rums are usually not a "vintage" product, they are usually a blend of different styles of rum from different batches and years, and aged in different types of casks. After blending, some are put back in barrels for a final finishing. These rums in some cases can be sipped, but also make great mixers for premium cocktails.
Aged or Dark Rums: These are the premier rums, the ones that have spent from 6 to ... years in barrels. Most are blends of different types and ages of rums to attain the flavor that the blender is seeking. You have to watch out for the age statement on many of these rums, but usually the age statement is letting you know that the youngest rum in the blend is at least that age. Many are age equivalents, these are numbers that take into consideration the environment that they were aged in. Many of these rums have some heavier post stilled rums in the blend, giving the finished product a higher viscosity and richer flavor. When you are looking at these rums it is the flavor of the expression that you are seeking, and not how old it really is. "Vintage" rums are the only ones that give you a true age, because they were from a specific year and production run. These rum are for sipping and generally not for mixing.
Flavored and Spiced Rums: The name says it all. These are the rums that usually not aged, but mixed with flavoring and or spices to give you a palatable flavor. Generally low grade distillate based, these are definitely mixers in most cases, but there are exceptions.I hope this helps you understand the differences in the rums that you see on the shelves and in the bars. The older the rum the more it costs to produce, and the more expensive it will be for you to taste. Hope you can get out and try some these expressions of the rum in the near future. ;o)
