I would recommend bookmarking the NGC website. The values are often inflated compared to say eBay but it's a pretty comprehensive reference for just about any coin you can think of. Here's the Zambia 5/-
If you ever need to determine if a coin is silver first find out the weight, (NGC doesn't usually supply this info. but other sites including Numista do) and check it using digital scales. If you don't have a set of these scales yet they can be picked up for under $20 and along with a 10X jeweller's loupe you have your basic coin collectors outfit!
Non illegitimis carborundum est. Excellent advice for all coins.
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