Zinc Alloy vs Aluminum: Which Sport Medal Holds Up? ⚖️

Both metals show up on every Thai medal quote. One feels like a real award. The other feels like a souvenir. Here is how to tell the difference at the casting stage.

Weight Is the First Tell

A 70mm zinc-alloy medal weighs around 90g — substantial in the hand, the heft that runners post about. The same dimension in aluminum lands closer to 30g and feels hollow. Aluminum has its place (kids' fun runs, throwaway giveaways), but for a finisher medal that needs to feel earned, zinc alloy wins every time.

Plating Sticks Differently

Gold/silver/bronze electroplating bonds beautifully to zinc alloy and stays color-stable for 5+ years indoors. On aluminum, the same plating chemistry needs a primer coat and still tends to dull within 18 months under Thai humidity. If the medal will live in a tropical display case, zinc alloy is the lower-risk pick.