Does the source of the address you have for Peter in 1900 also state his occupation or anyone else at same address? Mauriceville was one of NZ's main Scandinavian settlements 1870's-1890's. Mauriceville West mainly Danish and Mauriceville North mainly Norwegian.
You can search Historic NZ deaths online at BDMNZ. There is only about 30 odd Peter Christensen deaths recorded in the searchable dates. You could eliminate many of them as age at death would not match. https://www.bdmhistoricalrecords.dia.govt.nz/
This same website allows searches of historic marriages and births.
New Zealand also have Historic Newspapers that can be searched for free at Papers Past website. It can be a great source of information. https://paperspast.natlib.govt.nz/
You may have to look at different spellings when using these sites. Christiansen, Christianson, Christenson etc.