Can they be consumed raw, like Coca leaves, or are only when brewed?
Well yes Keith
The effects aren't in the same league as Coca though.
Generally I found anything other than very new leaves to taste quite bitter when eaten fresh though.
Some of the local groups ferment tea (similar principle to Sauerkraut).
If matured for long enough, the results can be good
Note the blade she tapes to her finger to help with harvesting.
2nd pic is part way through production (yes, we got to try doing each stage ourselves)