@zuz, first welcome to CCF. Second, it looks to me like this is a silver round, perhaps from the 1980s rather than a coin. I see, for example, that
APMEX occasionally has these for sale:
https://www.apmex.com/product/60643...illa-w-eagleAs such, I would expect that most of the value is in the silver bullion content (and nostalgia since this piece belonged to your grandfather).
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-----Ghanaian proverb
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