The recipe for "mormorion" requires a Aqueous whetstone instead of a Basilisk whetstone, like all the other gems of the surrounding levels:

Mormorion:
http://na.finalfantasyxiv.com/lodest...e/0a7452fce7c/

Now granted, it might be possible that it was intended for a totally different type of material to be required for this item but My guess is it's a bug/mistake.