We're going to try this for a while. The spell "mould ring" can now be cast,
in ADDITION to its normal version, at multiple gems.
cast mould ring at mould gems <list> material <band material>
Taking multiple gems might allow you to use a handful of smaller gems instead
of one big one, just bear in mind that there is a cap (saccing 50x black star
sapphires is wasted). It is also possible to experiment with splitting the gem
types for multiple smaller bonuses.
Again the original syntax should still work as normal, so the change is not
mandatory. But feel free to poke around with multiple gems, mixed type or same
type, and see if it's something you like.