its not silver that you see, just the remnants of the gold plating that you had on the earphone jack that you are refering to. the under layer is always copper or a amalgamated metal of sorts that has more conductance and less resistance, yes gold is better than silver any day because of its conductance compared to silver, gold is also known for its non corrosive nature in contacts, thats the reason you will also see gold contacts on most or all computer spares. you can get these replated
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