From Season 14 Mu Online has Improved Jewel Stacking System
Jewels no longer need to be stacked with Lahap NPC, now they are stacked right in the inventory, simply dragging jewel on each other.
Jewels can be disabled in inventory as well, using button Disassemble and left click on stacked jewels
This function does not costs zen
Maximum stacked jewel is 50
Jewels that is picked in game, stacks automatically
Chaos machine no longer needs un-stacked jewels, it will unstack automatically for mix and wont take more than required! For example you need 4 jewels for