The good Dr. Loosen - the historic Mosel estate credited by wine writer Hugh Johnson with bringing the region's rieslings into the 21st Century - is back in Pennsylvania's storehouses in a big way.

Those who have come to love Loosen for Dr. L, one of the world's great wine values, should take a small step up to explore the distinct terroir flavors of the "Slate" estate series. The "Red Slate" is the driest of the two, due to the steep cliffs of red slate earth in the Ürzig and Erden vineyards that foster racy minerals and spice, with just a ping of oak and lemon-curd sweetness to shade and round the finish. The "Blue Slate" Kabinett is also mineral-rich, but the heat-retaining blue slate of Bernkastel, Graach, and Wehlen draw a riper sweetness from the grapes, evoking apricots braced with tart apples and an elegant floral nose.

- Craig LaBan
Dr. Loosen Blue Slate Riesling Mosel-Saar-Ruwer Estate Kabinett QbA 2012, $18.99 (code 48437); Dr. Loosen Red Slate Dry Riesling Estate 2011, $13.99 (Code 48416.)