Note that you can make only one pure Oridecon or Elunium each time you talk to the NPC.
When you collect 5 Rough Oridecons and Rough Eluniums, you can convert them into a single Oridecon or Elunium by talking to an NPC in the upgrade shop.
6.3 Enriched Oridecon & Elunium + Enriched Refine Event.3.2 Refining Rough Oridecons and Eluniums.