@andretkj1 there's ~50 in the scene, possibly more on other shelves out of scene. even if we assume it's just the 50, bearing in mind he's not using magic to refine materials but outright creating hem from nothing, assuming he hasn't used part or most of his mana already for other tasks, and also assuming he hasn't leveled up since the last time we saw his stats (2 years ago in his world's time iirc), that's ~2 million mana per cup, though how much of that is going to materials and how much to the very fancy form I don't know...more likely though, he was already low on mana and/or there's a bunch out of scene cause he needs a LOT of tableware pieces for the party and doesn't have time to have it all done if he can ONLY make 50 per batch (...well, further assuming he makes one or maybe two batches a day, or unless his stats give him a faster mana recovery than the "mana fills to full once a day while you sleep" rule that seems most common)
lots of assumptions have to be right for that math to work out, and if anything except the no more level ups alone is wrong, then it's probably much cheaper than 2 million mana per