Is it correct to pronounce Shiraz with an emphasis on the "Z"? What about with a silent "Z"?

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Dear Dr. Vinny,
Is it correct to pronounce Shiraz with an emphasis on the "Z"? What about with a silent "Z"?
—David, Melbourne, Australia
Dear David,
Shiraz is the Aussie nickname for Syrah. It’s pronounced “Shee-RAZZ” in that Australian accent; here in the States the way people say it rhymes more with “pizzazz.” I also sometimes hear the second syllable a bit more softly, ending more in an "–oz" sound.
I have heard people drop the "Z" when they say "Shiraz," so that it it rhymes with "Syrah," but I think that's just a confusion between the two words.
—Dr. Vinny (DOK-tor VIN-ee)