As a title for an art exhibition, IMHO what is required here is something absolutely dramatic likely to attract a crowd.
Referring to the objects referred to, as Harry-san suggested, is the key to making a success of your function here, i.e. not just translate a word string, but to make it work as the key stone of the intended marketing pitch. This you will always do in all safety, by looking at the whole picture/functional context before jumping in. Don't agree?

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Note added at 19 hrs (2013-01-28 02:42:09 GMT)
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Oops! apologies for mixing my metaphores so dismally :-) :
"Key stones" don't ring out, so how could they have a "pitch"?
"Key note" would have been much better...

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Note added at 20 hrs (2013-01-28 04:08:24 GMT)
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(this is a 'resend'. previous did not register)

Oops! apologies for mixing my metaphors so dismally:
"keystone" does not echo the connotation that marketing "pitch" carries.
Let's make this "keynote" instead.