Sooo, um, I made an edit.
Because it's not 5 times force into an object 1/5 the size, it's five times the force unto the same object.
Once conjoined the gems are for all intents and purposes the same object, any force I apply to one is applyed to the other, not because it's transfered, but because it's the same object. Think Quantum entanglemnet.
The difference is that when I apply force to one gem, the force that the other gem feels is multiplied by their size difference.
It's not apply two newtons to the table, and one will get moved to the other table, it's apply two newtons, and the smaller "half" will act like it got five, while the larger "half" acts like it got one newton. No matter how far appart the two "halves" happen to be.
Does that make any sense at all or am I speaking Physics textbook?
Navani thinks it will be conserved
I've thought about this quite a lot and it doesn't make sense.
So moving the bigger gem is harder than moving the smaller one, and the smaller one goes further, and we must conserve force.
The only way I can think to explain how that works is that somehow there is a resistance mechagnism that will store the force applied to the bigger gem, and then release it into the smaller one. The question then becomes, how? and on what scale does it start?
Is it any movemnet at all, meaning that you have to give the larger gem several times the energy needed to move it before it actually moves?
And why does that deserve a reveal more dramatic than that of isolating planes of motion, and require more difficult to obtain materials?
Put it in the highstorm.