"He is delighted, very excited about it. We did show him the designs, the drafts and everything else," she said.
"This is our way to pay tribute to him. Madiba does represent something special, not only in South Africa. He is really an extraordinary human being."
Marcus made the first transaction with the new banknotes on Tuesday morning at the Lynnwood Housewives' Market, east of Pretoria.
"As far as I am aware, yes [I am the first person using the notes]. How privileged am I?," she said, laughing.
The governor was mobbed by reporters and camera crews when she went around the fruit and vegetable shop picking produce. She bought packets of nuts, beetroot, a sliced melon and a cucumber for R159.99.
Marcus said the new banknotes would be available at banks and automated teller machines later on Tuesday.
"We want to ensure that everyone is familiar with the new notes, whether you are in rural or urban areas, because we don't want anyone making a dummy of some kind," she said.
She said there were heightened security features on the new notes to avoid counterfeiting.
"It's hard to replicate. You have to feel the raised print, look for the watermark and if you tilt it you can see the moving colours," she said.
In September, the South African Reserve Bank launched a national campaign for the new range of banknotes honouring Mandela.
The bank said the range was themed "One of a kind" and that the campaign was aimed at educating the public about the banknotes.
The new R200, R100, R50, R20, and R10 notes show Mandela's face on the front, and the Big Five animals, which appear on the existing notes, on the back.
Security features include watermarks, micro-printing, and unique numbering. Raised printing was added to assist the visually impaired.
The new banknotes are the same size as the old notes, which will remain legal tender.
Marcus said that as at December last year, banknotes to the value of R100-billion were circulating within the South African economy. –Sapa