Blackboard-bold is common but by no means universal - plain old bold turns up in some works. Whatever the stylization the point is Q-for-quotient, not the font.
I've been inclined to think of it as a symbol based on a "Q" myself, though I admit the distinction is fuzzy, certainly it's still often written as a "Q" and pronounced as a "Q".
I know I know, I'm just making excuses for not having seen it. (There's one in the title of my PhD thesis, as it happens, and I remember being mildly unhappy that the bookbinder couldn't do blackboard bold on the spine!)
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Date: 2007-06-01 08:05 am (UTC)(no subject)
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