You wouldn't believe some of the stories I've heard, and I didn't believe them either. For that reason, until I can give you verified information about particular rums, I've chosen not to print anything at all about them. But one thing you can be certain of is that the research continues. The best rums are made under the strict supervision of an experienced distiller, from fresh raw materials. Some people swear pot-still rums are the best, but without the patience required to age these spirits they are not really special.
Rum gains a slight yellow to brown color as it ages in oak barrels.
But some rum is aged and then filtered to remove the color acquired during the aging process. And not all dark rums are aged. Distillers commonly add caramel coloring to their spirits to adjust the color. Sometimes this is just to compensate for the differences in the color of the rum from different barrels, at other times caramel is used to make the rum so dark that you can't see through the bottle. Rhum agricole is a spirit made in the French islands from fresh sugar cane juice.