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Dear Dr. Vinny,

Do you know the meaning of the letters and numbers listed on old bottles of Heitz? I have Cabernets with numbers of C-91 and MZ-1. The C-91 is vintage 1969 but the MZ-1 is non-vintage, and I've heard that it contains 1971 Martha's Vineyard. The Chardonnays from 1970 thru 1975 are marked with the letter Z and numbers but I have no clue what the "Z" means.

—Randy, Sonoma, Calif.

Dear Randy,

This question was a fun one for me to research, and I got the answer from Kathleen Heitz, daughter of founder Joe Heitz, and former president and CEO of the legendary Heitz Cellar winery in California's Napa Valley, which was recently sold to new owners.

Kathleen explains that the “Z” on the Chardonnay refers to the location of the vineyard on Zinfandel Lane, which is absolutely the real name of a road in St. Helena.

“The original land holding there was owned by a few friends, including my father," she says. "When some of the partners wanted out, Joe purchased the vineyard on the south side of the road and someone else bought the piece on the north side of the road, which has been sold a few times since then.” She adds that she believes this is the vineyard where the grapes from a Los Angeles Fair best-in-show award-winning Chardonnay came from, so her father liked to put the “Z” on the bottle to denote that pedigree. Interestingly, one of the most important brands in Napa Cabernet first got attention for its Chardonnay.

There wasn’t any code to break with the “C,” but Kathleen confirms, “The C-91 is a blend of mostly 1969 Martha’s Vineyard and is a fabulous wine. [Having just started the business, Joe was] a bit short on cash and so took one of the lots of Martha’s and sold it a bit early to generate cash flow for upcoming projects. Those in the know stocked up their cellars with this one.”

And finally, says Kathleen, “The MZ-1 was a blend made and sold as we declassified Martha’s Vineyard [in 1971] and did not produce a 1971 Martha’s Vineyard. This would not be in the same league as the C-91.”

—Dr. Vinny

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