The phrase "about the boldness of" is correct and usable in written English.
It can be used when discussing or analyzing the quality or characteristic of boldness in a particular context or subject.
Example: "The article explores the boldness of the artist's latest work and its impact on contemporary art."
Alternatives: "regarding the audacity of" or "concerning the bravery of".
Writer friends have often raved about the boldness of its narrative technique.
Its Democratic mayor, John Norquist, is about to be re-elected for a fourth term.Yet there can be no doubt about the boldness of the city's experiment with vouchers.
And the painting, entitled Hope, it's about the boldness of a girl to believe that even when blinded, even with a broken heart and only one string, she could still play music.
Think about the boldness of the NBA's resolve here.
Everyone was talking about the boldness of the ad, the creativity of this method of launching a new product.
The text of Āzād's speech was printed the next day in a local newspaper, and there is no doubt about the boldness of his message: he called for a new Urdu poetry and a new poetics, both based on English models.
Vanessa teaches me about the definition of elegance right now, and about the gestures — the boldness of an earring, the skinniness of a trouser — that make all the difference ("Styled to a T," "The Velvet Revolution," and "Eye Intensity").
One of the best things about the novel, apart from the boldness of conception, is its lack of cleverness: there's a bare minimum of winking.
Structurally and tonally, they create an arch form, but what's most striking about the whole work is the boldness of the scoring.
The book also places museums in the context of the cultural politics of the progressive movement illustrating the limits of progressive ideas of democratic reform as well as the boldness of vision about cultural capital promoted by museums and other cultural institutions.
But note the empty inflation of "key", begged questions about how "senior" or how "sub-clinical", and the boldness of "showed".
