Answer: The “very” before “unique” needs to be removed.

Explanation:
Here’s the formal argument: Something that’s unique is one of a kind — there are no degrees of uniqueness possible.

Here’s how Paul Brians explains it:

“Unique” singles out one of a kind. That “un” at the beginning is a form of “one.” A thing is unique (the only one of its kind) or it is not. Something may be almost unique (there are very few like it), but nothing is “very unique.”

Opinions to the contrary exist.

Seth Golub, for example offers the argument that there’s nothing wrong with “very unique.”

“I wrote this more than ten years ago, mostly to poke fun at the legions of more-pedantic-than-thou prescriptivist grammar dweebs of the world. I occasionally get email about it, mostly “right on”, occasionally “you’re a moron”. I think anyone who cares strongly either way should probably take a deep breath and go for a walk. ”  >  Read on

What to do?

Wherever you stand on the acceptability of “very unique,” there’s no need for the “very” — and, as such, it doesn’t belong in formal writing. O/w, though, sure — go ahead and use “very unique.” Just be prepared to have some people think you’re stupid.

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