What are the grapes used in the white wine blend named Conundrum?

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Dear Dr. Vinny,
What are the grapes used in the white wine blend named Conundrum?
—Juan, Chicago
Dear Juan,
Conundrum—the white wine blend created by the Wagner family of Caymus Vineyards (though it is now bottled as a separate label) is really a unique wine—fragrant and juicy and unlike anything else out there. It’s a secret recipe in the sense they won’t share percentages of what makes the wine up, but they do confirm that it’s a blend of five grapes: Chardonnay, Sauvignon Blanc, Muscat Canelli, Viognier and Sémillon.
—Dr. Vinny