If you are the kind of person who's irritated by people grabbing your hand at parties and cooing, "Where did you get that ring?" you should think twice before purchasing jewelry by Claudia Kussano. The Mission-based jeweler was trained as an artist in her native Brazil, which may explain the tactile, exotic appeal of her pieces. Certain biomorphic shapes repeat in her rings, earrings, and necklaces — ferns, petals, sprouts, twigs — but this isn't hippie twee stuff. Instead, the shapes are pared down to a minimalist elegance, emphasized by the patina of sterling silver, Kussano's favorite metal. She also experiments with unusual material combinations such as sequins and horsehair. The storefront on Guerrero is as spare as an art gallery, with jewelry hung from tree branches and resting in papier-mâché pods and on silk leaves. If the crop of offerings doesn't please you, Kussano can whip up a custom piece to reflect your true nature.