Hookah coconut charcoal is the most popular type of coal nowadays. It is usually pressed into cubes of 22 or 25 mm or long triangular bars (popular in Brazil and Latin America).
In production it does not use any chemical additives or nitrates. Manufacturers of coconut charcoal is often proudly mention at the packaging "100% eco-friendly", as they use the unused rests of coconut shells.
How to light Coconut charcoal for Shisha
To ignite the cube of coconut charcoal, matches or lighter will not work. It takes longer time and additional spiral stove or gas burners to heat up the charcoal untill it become red. However, the results are worth it: you get a clean taste, smooth tobacco heating and no headache after hookah session.