Quartz-crystal devices are disclosed, of which the CI value is reduced by adjusting the shortest distance between an edge of electrically conductive adhesive and an edge of the excitation electrode. The device has a quartz-crystal plate having long-edges and short-edges. Excitation electrodes are on first and second surfaces of the plate. Conductive pads are electrically connected to respective excitation electrodes and extend to the short-edge of the quartz-crystal plate. A package having a pair of external mounting terminals and respective connecting electrodes are situated on opposing sides of the mounting terminals for making electrical connections to the mounting terminals. An electrically conductive adhesive bonds the connecting terminals and respective conductive pads together, and the quartz-crystal plate onto the package. The shortest distance between an edge of the adhesive and an edge of the excitation electrode is 10%-15% the length of the quartz-crystal plate in the long-edge direction.