Ok, so at about 4mm they’re not record breaking, but I couldn’t find earring findings with trays any smaller. Cedar ply with an MDF core, engraved with cuneiform signs (the star sign translates as “god/ess”, the other one is “mother”).
Earring cards also made on the GF! Having lots of fun designing packaging to eat into my stache of Amazon boxes…coughpandemicshoppingcough

Edit: just realized there are three designs here, not two! The one that starts with a triangle shape can mean several things, including “queen” and “sister”.