THE NEW gallery season got off to a roaring start this week with 20 joint exhibition openings in the Dupont Circle area, a half-dozen more in and around 406 Seventh St. NW, and others in Georgetown and elsewhere around town.

One of many good places to begin a fall tour is at Tartt Gallery, where Gayil Nalls is showing 12 gilded wood panel paintings that include some of her strongest, most mature work to date.

A bright, versatile artist who lives and exhibits both in Washington and New York, Nalls was last seen here at Brody's Gallery in a show of cast bronze sculptural vessels, the varied patinas of which rekindled her interest in using gold and silver leaf in her paintings. But now her interest was in something more than a background glow; rather, she sought to make painted surfaces which, like metal sculpture, could darken, deepen and change over time. In doing so, she has given new life to the medieval water-gilder's art.

An artist who deeply respects the power and grandeur of natural forces, Nalls manages, in these new paintings, to harness some of that power and put it to work in deliciously smooth, highly reflective works that change not only over time, but in varying light as well. The star of the show -- "Silhouette 5," a semi-abstract floral vessel -- is a shimmering wonder in which even the colors seem to be in a state of perpetual transformation.

Using only materials that are of the earth -- or "alive," as she puts it -- Nalls produces these little natural-energy generators through a complicated process that requires painstaking craftsmanship as well as imagination. First, she paints her subjects onto 24-inch-square wood panels, using a brush and natural clay pigments dissolved in heated rabbit-skin glue, exploiting the broad range of hues the earth provides, from ordinary ochres and terra cottas to surprisingly rich, deep plums, and brilliant blues and greens. Then, with the painted image complete, Nalls covers it with squares or strips of thin white or yellow gold leaf, and burnishes it with an agate. With the mosaic-like gold overlay in place, she then completes the painting by using a fine pumice stone to scratch through the layer of gold, excavating and transforming the painted image underneath.

The results are tremendously varied, as is the show itself. For to the dismay of her dealers, Nalls will not (and may never) settle on a single, hallmark style of painting, and, in consequence, there are works here that range from the aforementioned hard-edge, semi- abstract flower in a vase to the brushier, more realistic "Thistles" hanging next to it, and on to the minimal, oddly haunting "Washington Silhouettes," which summons up a sense of impending disaster. There are also two strong, highly expressionistic landscapes painted on site during a stormy sunset over Cape Cod Bay, which somehow remind us that we should go back to the Phillips and take another look at how Augustus Vincent Tack handled his unique combination of precious gold and violent landscape.

Other paintings -- less interesting ones, from this view -- reflect Nalls' ongoing interest in making icons of her own personal symbols. Most of them are undecipherable, others just plain goofy, notably a saucer-eyed humanoid titled "Remain True to the Earth." That title, however, serves nicely as a credo for Nalls, and goes a long way toward summing up the impulse behind the paintings in this show, which continues through Oct. 17.

Tartt Gallery is at 2017 Q St. NW, and the hours are 11 to 5 Tuesday through Saturday.

For anyone lucky enough to have seen the aboriginal cave paintings of Australia, Dorothy Preston's new oil paintings at Franz Bader Gallery, 1701 Pennsylvania Ave. NW, will swiftly recall them. For others, however, the paintings manage somehow to conjure up a visceral sense of what those cave drawings are about, of their magical, dreamlike quality, and the elemental belief in spirits that propelled them.

Though based on a long and obviously sensitive and respectful study of these caves and their meaning, these are in no way clinical representations. Rather, they set out to evoke the spirit figures, the elongated animals and petroglyphs that Preston observed during her years in Australia. The dry, chalky texture reinforces the sense of ancient walls.

There are stencils of human hands that convey an eerie sense of ancient presence, and shadowy overlays of floating whales and kangaroos that seem to inhabit the world of dreams. Some unrecognizable animal and spirit figures seem almost to have been shaped with the help of some outside force guiding the artist's hand, so convincing are they. There is even an X-Ray Kangaroo, reminiscent of those from Arnhem land, potent evidence of the richness of the aboriginal intellect as well as the imagination.

The show will continue through September 26, from 10 to 6 Tuesdays through Saturdays.

The Bader Bookshop, by the way, has moved out, and will reopen in late September at 1911 "I" St. NW.