This won't make you a lot of gil, but it is a quick way to make gil and level up non crafting gathering classes.
Your leveling roulette will give you cracked clusters you can trade in for materias that can sell for a lot, just check on your market boards to see what's selling for a lot. (Trade in located at rhalgrs reach)
Roulettes give you among 10,000-15,000 gil each time. But that is just for roulettes , not for after you've received your daily allowance.
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How to get Gil quickly on Final Fantasy XIV
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