The coquina is created when bewitchment is generated the world in the following two conditions
The biome must be ocean or beach
There must be a block of sand
Since the configuration specifies dimension 20 (the betweenlands), this condition does not occur because the ocean is being replaced by deep water and Silt Beach biome
The coquina is created when bewitchment is generated the world in the following two conditions
Since the configuration specifies dimension 20 (the betweenlands), this condition does not occur because the ocean is being replaced by deep water and Silt Beach biome