The gold iPhone 5S is such a hit with consumers that Apple has asked suppliers to boost production of the phone by one third, according to a report.

The report, on The Wall Street Journal's Digits blog, cautions that "it isn't clear whether there are currently supply constraints" around manufacturing the new iPhone. Apple reps declined comment on the report.

Word leaked out in August that Apple planned to offer a gold iPhone. Gold is one of three finishes offered for the 5S, in addition to silver and "space grey." The colors distinguish it from the 5C, which comes in red, yellow, blue, green and grey. The higher-end 5S retails for $199 to $399 with a contract (depending on the amount of memory), compared to $99 to $199 for the 5C.

With both models on sale Friday, analysts expect Apple to sell between 5 million and 8 million of the new phones over this coming weekend.

Image: Getty/Glenn Chapman