As a way of ending our time together, I somewhat sheepishly asked him something I have asked no one before or since: Could I have his autograph. As he wrote, it became apparent that he was doing more than merely signing his name. He was writing what turned out to be a lovely note. The problem was, only part of it was on the piece of paper I had given him. The rest of it was on the tablecloth on which the paper was resting.
His eyesight, badly affected by years of working in the limestone quarry on Robben Island, was unable to distinguish where the white piece of paper ended and the white tablecloth began.
How do you tell the last great icon of the 20th century that he is writing on the tablecloth? There was nothing that I could think of except just that: "Madiba, that's the tablecloth you are writing on.'
His response was an apology and a face creased with concern, before finishing what it was he wanted to write, this time on the piece of paper I had given him.
During our chat, he sat bolt upright. That fabulous Mandela posture. He was solicitous, deferential. He gave every good impression of being an Edwardian gentleman having an audience with the Queen.
Nine years later, in 2004 in South Africa, I heard South Africa satirist Pieter Dirk Uys ask a Cape Town audience "what would have happened to South Africa, and to you'', _ the audience was almost entirely white - "if Nelson Mandela had come out of jail angry?''
The answer was missed by no one: South African history post 1990 would have been very different.
The so-called bloodbath that many supporters of New Zealand's sporting contacts with apartheid believed would follow the end of apartheid never eventuated. It was Mandela's personality and policies, and his ability to recognise the power of the unifying, symbolic gesture which were in very large measure responsible.
In the four years between his release from prison and assuming the presidency, Mandela's hand reached out to Afrikaner nationalists in a spirit of reconciliation.
He visited Betsie Verwoerd, widow of the architect of apartheid, Hendrik Verwoerd. Most extraordinarily, he met Percy Yutar, the judge who had sentenced him, and his Rivonia trial colleagues, to life imprisonment.
As President, Mandela sought to unite and play down divisions. He argued in favour of the national rugby team retaining their Springboks name. On the day South Africa won the 1995 Rugby World Cup, he wore Springboks captain Francois Pienaar's spare No 6 jersey.
When a Pretoria policeman was found to have a computer screen-saver of a gorilla's face morphing into that of Mandela, the President's response was to laugh and declare, "but every gorilla wants my face'.
Within two years of Mandela's presidency, the threat posed to the new South Africa by white extremists had evaporated.
Equally, his hand reached out to black rivals. He brought Chief Buthelezi into the 1994 Government of National Unity, giving him an important cabinet post. The bitter struggle between Mandela's African National Congress (ANC) and Buthelezi's Inkatha Freedom Party, the so called 'black on black violence' which had claimed 25,000 lives between 1983 - 1996, was over.
But the role that Mandela played in the period following his release from 27 years in prison is only one aspect of his legacy. Mandela won the presidency in 1994, and was able to command the respect of a large majority of South Africans, precisely because of what he had been in the first seven decades of his life.
Over a period of more than 20 years, from the early 1940s to his imprisonment on Robben Island in 1964, the role played by Mandela, Walter Sisulu, Govan Mbeki, Oliver Tambo and others was game-changing. They turned a largely ineffective and moribund ANC into an organisation which was critical to the path South African history was to take.
Their objective was both simple and noble, expressed most clearly in the words of the 1955 Freedom Charter: 'We, the people of South Africa, declare for all our country and the world to know: that South Africa belongs to all who live in it, black and white, and that no government can justly claim authority unless it is based on the will of the people.'
In 1960 the ANC was banned. In 1963, Mandela and nine other ANC leaders were charged with 221 acts of sabotage designed to overthrow the apartheid state.
In 1964, at the conclusion of the Rivonia trial, Mandela was sentenced to Robben Island for life. He spent 18 of his 27 prison years on the Island in a cell I remember describing to TV3 after a visit there in 1996 as "not much bigger than a matchbox''. The floor was Mandela's bed, a bucket was his toilet. He was allowed one 30-minute visit a year. He could write and receive one letter every six months.
When he walked out of jail a free man on 11 February 1990, the path ahead for Mandela, for the ANC, for South Africa itself, was all in the balance. Many future paths were possible.
Mandela had gone to prison a firebrand but came out believing that the way forward was via a negotiated settlement, that compromise was inevitable. Many in the ANC were unprepared for this. It was a very difficult time for Mandela, and for the ANC.
He was accused by some of being a sell-out, but there is a limit to how effective that charge can be against someone who has just spent 27 years in prison, even if he did seem to be turning various established ANC positions on their head. Revolutionary, hard line positions were rejected. Mandela's position eventually carried the day.
The belief persisted, however, with some that the ANC had given too much away. In this transitional period, the ANC agreed, for example, that the new South Africa would be built on the socio-economic foundations of its predecessor, something which certainly ran counter to their established socialist economic thinking of the time. Today, some argue that in determining this, the seeds for much of what has gone wrong in the new South Africa were being sown.
But in the heady, dangerous climate that permeated the 1990 - 94 period, when massacre followed assassination, when Armageddon seemed at times to be only a month, a week, a day away, the hard line approach seemed to offer only greater uncertainty, greater danger.
How great is Mandela?
Had he been sent to the gallows in 1964, he would probably be regarded today as a colourful hero, one of many in the ANC's long history. What a difference 27 years in prison can make.
The 19th century view that history was no more than the sum total of the lives of great men finds few if any believers today. But Nelson Mandela is proof that, just very occasionally, an individual can take history by the scruff of its forces (I don't think history actually has a neck), and achieve remarkable results.
By the time of his release from prison in 1990, Mandela personally embodied major strands of those forces. This, combined with his humanity, political astuteness and a refusal to ever lose sight of the major goal (the opening stanza of the 1955 Freedom Charter), enabled him, against huge odds, to establish the foundations of a rainbow nation.
Nelson Mandela's impact on 20th century South African history is without equal.
• Trevor Richards was national chairman of the Halt All Racist Tours movement from 1969-80, then its international secretary. He is author of Dancing on Our Bones, a history of NZ sporting relations with apartheid South Africa.
