It was the white iPhone 4. And it was delayed almost a year (10 months)
There was a problem with the flash and white back glass combo so Apple changed the glass and paint and launched the white iPhone 4 in April 2011 (the black one was launched in June 2010) and because of those changes the white one was actually a little thicker than the black one.
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I owned a black iPhone, iPhone 3GS, iPhone 4, iPhone 5, iPhone 6 and 6 Plus.
The only white bezel iPhone that I had was the Gold 5s.
IMHO, black bezel devices look much better.