Quartz

Quartz is a piezoelectric crystal: when electric current passes through it, it vibrates at a constant and measurable frequency. This physical property is the foundation of nearly all non-mechanical watches produced today. The standard reference frequency is 32.768 Hz, chosen because it is the fifteenth power of two and divides easily into fractions of a second through a digital divider. The resulting signal drives the stepper motor that moves the hands.

The difference between 32 kHz and higher frequencies is no small detail. The Bulova Precisionist oscillates at 262.144 Hz: the seconds hand sweeps continuously without the typical ticks of ordinary quartz, and the stated accuracy drops to ±10 seconds per year versus ±15–30 for standard calibers. An even more significant leap is made by thermocompensated SuperQuartz, which automatically corrects the frequency drift caused by temperature variations: under real-world conditions of use, it comes closest to the precision of radio-controlled signals without depending on external reception.

The meca-quartz movement deserves a precise distinction. It is neither purely electronic nor mechanical: the quartz handles basic timekeeping while a separate mechanical module operates the chronograph. The practical result, visible in Seiko Instruments' VK64 or Depancel's VK63, is a chronograph hand that sweeps fluidly during counting and returns to zero with the crisp, clean snap of column-wheel mechanisms. Neither world is entirely sacrificed.

Grand Seiko's Spring Drive occupies yet another distinct position. It uses a mainspring as the energy source, so it does not depend on a battery, but regulates release through a quartz oscillator and an electromagnetic brake called the Tri-synchro Regulator. The stated accuracy is ±1 second per day, achieved without the typical compromises of either purely mechanical or purely electronic watches.

Quartz also appears as a structural and decorative material. Aventurine is a variety of quartz with mica inclusions that produce the sparkling effect of so-called galaxy dials. Tiger's eye is a fibrous quartz with chatoyancy, that is, the moving-band optical effect that changes with the angle of light. The forged quartz used by H. Moser & Cie. in the Streamliner Pump is instead a technical material obtained through fusion and compression, employed as a case element. Different stories, same starting mineral.

From the workbench I add something magazines tend to overlook: the quartz crisis of the seventies was not only a Swiss affair. It struck every market that had built an industry around affordable mechanical movements, from India to Japan. Those who survived did so either by betting on mechanical luxury, as Switzerland did after 1985, or by embracing quartz as their own technology, as Seiko did. The middle roads disappeared.