There are no circulating coins today, Finn, that are made of silver. There are non-circulating coins made for collectors and investors that contain silver, but regular circulating coinage today contains no precious metal. Too bad.
As such, the 5 cent coin with the tuatara lizard is made of copper nickel and is worth face value.
If you can find a fully uncirculated specimen, a collector might be willing to buy it from you for a few US dollars.
However, there is a twist with NZ 5 cents dated 1967. If you are lucky, your coin may be the 'no sea' variety. Check the side-by-side comparison image below. If you have a 'no sea' coin, then catalog values run like this:
1967 'NO SEA' VARIETY
worn: $2 US dollars approximate catalog value
average circulated: $5
well preserved: $15
fully uncirculated: $40
As always on CoinQuest, these are catalog values and must be adjusted to obtain actual buy and sell values. Read our Terminology page to understand how to make this conversion.