Mangrove Bark
From Cargo Handbook - the world's largest cargo transport guidelines website
The bark of the mangrove tree usually shipped in bales and bags and used extensively in the tanning industry.
Water damage affects the bark as the tannin content is decreased. Mangrove is grown in salt-water swamps and would give a salt reaction to an analytical test. Bags may be stained due to natural sweat or the moisture content of the bark at the time of packing. If the bags are contaminated by complete or partial immersion they become stained dark red up to the bag ears, a phenomenon which could not be produced had the staining been due to the natural moisture content of the bark.