The friendship that developed with Chelot was the initial impetus for Blume's new book, "The Master of Us All," which borrows its title from designer Christian Dior's description of Balenciaga.
The Spanish-born designer, who was one of the world's top couturiers for decades, opened shop in Paris in 1936. Chelot, one of his first employees, worked there until Balenciaga abruptly closed his operations in 1968. The designer died four years later in 1972, aged 77, and his label was not revived until 1986.
Despite Balenciaga's renown as a meticulous designer whose clothes were worn by royalty, socialites and Hollywood icons, he remained a mysterious figure.
Blume, a former columnist for the International Herald Tribune, spoke to Reuters about the designer, his business and how her conversations with Chelot more than 40 years after meeting her helped to reveal Balenciaga's personality.
Q: You knew one of the women featured in the book, Chelot, but what made you want to write about Balenciaga?
A: "After the house closed, I saw Florette very infrequently. (But) in the last few years of her life, she spent more time in Paris, and perhaps ... when you get to that age, you think more about what you've been doing. She realized she had been a witness to every minute of the house of Balenciaga in Paris.
"Everybody agrees (Balenciaga) was the greatest designer of the second half of 20th century, but he is also the most unknown. His character is always very cloudy on account of never accepting to see people, so he became known as this boring monk. So this seemed pretty intractable. But ... if you look at him, in the workplace, and you see the place as a workplace rather than as a cathedral or a shrine, then something comes out."
Q: What did you learn about Balenciaga's personality that surprised you?
A: "So many people said he had a very good sense of humor, and liked to smile, liked to joke, because he does seem very austere and strict. It's a strange thing. He was so kind to the models, and so awful, frequently, to the vendeuses (saleswomen).
"I managed to speak to a few of his friends, and ... they all seemed to agree about his charm and his humor, and the fact that he really basically only talked about fashion, but not in a gossipy way. The person who helped a great deal was (designer Hubert de) Givenchy, who, I think, spoke about him very well."
Q: Can you tell me about the fashion shows of the time?
A: "(My friend and I) just wandered in and we must have been a strange pair - palpably not potential clients. But you just went in. The other day I went to the Chanel collection here, and what a difference, all the guards, and they show only once, not every day.
"But it's a show, a real show ... and they weren't before. They were just girls marching out, turning and going back. It happened every afternoon for a month or so after the real (clients) had been there."
Q: After his death, do you think his family felt conflicted about the Balenciaga business becoming a larger industry, more a brand, instead of about Balenciaga the man?
A: "I don't know how conflicted they felt. I'm not criticizing them for what they did, to continue it even though they must have guessed that he would hate that ... but if they're feeling conflicted now it's because they sold too soon. And that sounds like a mean comment, I don't mean it as such. (But) suddenly the name is alive again, and they have nothing to do with it."
Q. Alexander Wang, the new creative director of Balenciaga, is known for being extremely outgoing, and for his downtown Manhattan style. What do you think of his selection?
A: "(Fashion writer) Suzy Menkes made a very good point when she wrote ... that he speaks perfect Mandarin. Since Balenciaga has 20 some odd outlets in China and is hoping to have more, this is a help. It'll be interesting to see what he does, because I don't think it'll be Frenchified."
(Reporting By Erin Geiger Smith; Editing by Patricia Reaney and David Brunnstrom)