Brown powder

Brown powder, often referred as "cocoa powder" due to its color, is an explosive agent similar to black powder, but with a slower (and therefore gentler) burning rate. This difference is achieved by incorporating fuel ingredients that are in a less-reactive state; the pulverized and fully processed charcoal (elemental carbon) in black powder provides its distinctive color while its replacement with a different substance produces a more reflective powder, hence its own namesake color. Further modifications of burn rate are made possible by shaping the individual powder grains, often into prismatic shapes such as single-perforated hexagonal or octagonal prisms. [Davis, T. L., Chemistry of Powder and Explosives.]

For pure explosive damage, high burn rates or detonation speeds (and accompanying brisance) are generally preferable, but in guns and especially cannons, slower-burning powder decreases firing stresses. This allows for lighter, longer (and more accurate) barrels with associated decreases in production and maintenance costs.

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