The biggest little museum in Washington has done it again. Two new one-woman shows at B'nai B'rith Klutznick Museum, in utterly different media, resonate within themselves and with each other as they explore the joy and pain of the Jewish experience.

Paintings by Mindy Weisel, born to Auschwitz survivors in the Bergen-Belsen extermination-cum-refugee camp, evoke somberness and sunshine in turn. Although the works are all quite recent, her dark and light moods are so distinct in style that the only common threads are skill and boldness.

Fiber sculptures by American-born Laurie Gross are equally bold and wonderfully disciplined. Confining herself almost exclusively to the basic shape of a draped prayer shawl, Gross weaves in themes of Jewish history and culture that add richness and depth of meaning.

The strength of both shows is such that you don't need to know anything about the artists or Judaism to feel the power of the work, although non-Jews will particularly appreciate the brief and excellent guides prepared by Linda Altshuler, the Klutznick's new director. The exhibition designs are another pair of jewels by Chris White, who long ago mastered the limited and awkward spaces of the museum.

An odd aspect of Weisel's painting is that her oils, while sometimes overpainted in several layers, are likely to be taken for watercolors, or even chalk or charcoal, at normal viewing distance. Her watercolors, on the other hand, have much of the depth of tone and firmness of line of oils.

There is not, in the selection presented here, any "intermediate" work. All is darkness or all is light, as though on different days different people stood before Weisel's easel. Of the two, the sad person seems more certain of her self.

Gross risks repeating herself each time she undertakes another interpretation of her prayer-shawl motif, yet the result is repeatedly original. It is the more astonishing because her works are simple to the point of severity, allowing no evasion or disguise. While each of the sculptures stands alone, they hang together even better.

Recently Gross has begun to experiment with variations on the kapporet, the valance above the curtain of the Ark of the Torah. It is a much less expressive and plastic shape than the shawl, and seems an unpromising line to pursue. But this is an artist who plainly knows what she's doing. TRANSITIONS and A THREAD OF BLUE -- Through September 5 at B'nai B'rith Klutznick Museum, 1640 Rhode Island Avenue NW. Open 10 to 5 Sunday through Friday (closed holidays). Interpretive tours available for groups. 857-6583.