Converting raw materials into sickles and knuts and galleons is a very precise process- but things get tricker when it’s coming from jewelry with various stones set inside it and not bullion. And even then, if you work at Gringotts, you’ll need to be fast and accurate when you’re identifying what each piece is made of. Most dwarves are raised to have a uniquely sharp eye for this very thing. So when a new teller categorizes something incorrectly, a dwarf would certainly be able to notice the mistake from a mile away…and such a mistake might surely be irritating to them. At least… it seems to be for this particular fellow. His rage can hardly be hidden- not even behind a solid wood counter. -A

↓ Transcript
BANK TELLER: Silver…
BANK TELLER:...zirconia...
BANK TELLER: ...silver...
BANK TELLER: ...gold...