Sparkly round

A sparkly round is the in-universe term the character use for a coin.

Yum lends hers to Mia who lends it to Touki without permission. Touki loses it and Yum blames Mia.

Mr. Mole doesn't seem to know what they are for (or doesn't want to explain currency) and he finds a 2nd one which he trades to Touki for a medallion he finds.

Yum forgives Mia though it's unclear whether she saw the coin first before doing so.