right place, right time

Signet ring?

@Davezilla Not sure it is meant to be used like that. But if I had the means to acquire this I would certainly ask the seller which materials would be safe to press my new caterpillar logo into.

https://mltshp.com/p/1PDWU

Intaglio (this stone cutting technique) rings were indeed used to make seals in hot wax in ancient Rome. A signet ring may also be solid metal.