Surname of “Black” from death record of wife Joan Doreen Black found in death search on New Zealand BDM website in January 2024:
2006/4722. Black, Joan Doreen….

No record of marriage to Joan Doreen Heaps could be found on the New Zealand BDM website as at January 2024.

First two given names, date and place of birth and death, date and place of burial, occupation, from Find a Grave website found in July 2025:
https://www.findagrave.com/memorial/141936293/alexander_william-black
Name: Alexander William Black
Birth: 4 Jan 1926, Christchurch, Christchurch City, Canterbury, New Zealand
Death: 1 Dec 1990 (aged 64), Christchurch, Christchurch City, Canterbury, New Zealand
Burial: Linwood Cemetery, Linwood, Christchurch City, Canterbury, New Zealand
Plot: Block A. Plot 508
Gravesite Details
Surname: Black, First name(s): Alexander William, Date of death: Saturday, 1 December 1990, Cemetery: Linwood, Date of burial: Thursday, 13 December 1990, Block number: Ashes, Plot number: 508, Age: 64 years, Occupation: Retired Technical Officer.

Place of birth confirmed from the New Zealand Birth Index found in August 2025:
Name: Eva Rosina Alberta Ward
Registration Place: Christchurch, New Zealand
Registration Quarter: Apr-May-Jun 1904
Folio Number: 2257

Name of parents from birth search on New Zealand BDM website in August 2025:
1926/14938. Black, Alexander William. Mother: Eva Rosina Alberta. Father: Alexander

Full date of birth of 4 January 1926 confirmed from further searching in August 2025 on BDM Search by incrementally changing the date range for the birth.

Year and country of first marriage from search on New Zealand BDM website in July 2025:
1948/13305. Bride: Iris Kathleen Walters. Groom: Alexander William Black

Full date of marriage of 6 November 1948 from further searching in July 2025 on BDM Search by incrementally changing the date range for the marriage.

Divorce granted in 1952 for first marriage as per a 'Restricted' record titled, "Black, Alexander William v Black, Iris Kathleen and Broadhurst, Ian George", ID R20363010, in the Christchurch repository, found in Archives New Zealand Collections in July 2025.

Remarried as at 1957, New Zealand Electoral Roll - Lyttelton Main Roll 1957, found in July 2025:
Black, Alexander William, Gebbies Pass, No. 2 R.D., radio technician
Black, Joan Doreen, Gebbies Pass, No. 2 R.D., married

Alexander divorced from his first wife in 1952. Therefore married Joan circa 1955.