Would there be any significance to the fact it was minted at the Heaton mint?
Not really, no. Heaton Mint made a lot of coins for the colonies. As you can see from the table on the page John1 linked to above, 1897 coins were struck in both London and Heaton, and the mintages from Heaton and from London are about the same. Their catalogue values are the same, as can be seen on the NGC database
In terms of value, it's probably about a US$30 coin.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis