A past Capital A project, John Hutchins’s Diggers, Constables, and Bushrangers, got a good review from the Journal of Australasian Mining History (vol. 10, 2012):
Hutchins’ book has the added value of clearly placing New Zealand as a small but significant link in the international sequence of nineteenth century gold rushes.
See also this post by Jonna about this book from a couple of years ago.