You can say that, but the drop chance should be very slime.
The mission can drop lowest level crystal to highest one so you can slowly farm it when have time.
You don't need to go to the broken aqua-boss map for farming, just last map is enough.
And... time to break gems and drink stamina pot for wealth is near hahahahahaha.
You can buy three of the rainbow gems per month with the medals if you're too unlucky on drops.
Nutaku: July 2016 | Flower Knight Girl: 835228859 | DMM: 646263953 飢えたハンター
Plays Flower Knight Girl, Aigis, Kamihime
Dropped Harem Heroes. Staff deleted my nice reason for not spending $.
Signature made by Myrdin
Daisy had the closed eye smile? shoot, almost had 5 LOL
Nutaku: July 2016 | Flower Knight Girl: 835228859 | DMM: 646263953 飢えたハンター
Plays Flower Knight Girl, Aigis, Kamihime
Dropped Harem Heroes. Staff deleted my nice reason for not spending $.
Signature made by Myrdin
Dear friends, It's time to use all thoses stamina potions gather with that Nazuna campain to become rich with Mori Mori stage!
May gold and stam' flow!
edit: you can get 57077 gold at max if you're lucky. That's a lot of gold.