I won’t assert that the Diatom Bar-M Chardonnay 2018, Los Alamos Valley, is the best chardonnay I’ve tasted this year, but even framing the issue in that parameter implies that it’s a pretty damned good chardonnay. Made by Greg Brewer, of Brewer-Clifton — acquired by Jackson Family Wines in 2017 — this Diatom ’18 was fashioned in small stainless steel tanks; malolactic was inhibited. The result is a chardonnay of stunning purity and intensity. The color is pale straw-gold; immediately attractive aromas of pineapple and grapefruit, green apple and cloves are enveloped in a haze of talc, honeysuckle and damp flint. On the palate, this chardonnay — delicate as a seashell but displaying plenty of energy — hovers in exquisite poise between an almost powdery texture and bright, vivid acidity, so the effect is spare, dry and elegant, yet with a back-note of ripe, cushiony stone-fruit flavors; a tide of limestone sweeps in from mid-palate back through a chiseled and well-defined finish. 14.5 percent alcohol. Los Alamos Valley lies between Santa Maria Valley and Santa Ynez Valley in Santa Barbara County; it is cooler than Santa Ynez and warmer than Santa Maria. Now through 2021 or ’22. Excellent. About $30.

Tasted at a distributor’s trade event.