A rounded semi-precious stone or synthetic material usually black, fitted into the watch crown as an ornament.
A watch feature that shows the date and sometimes, the day of the week and the month. It can be displayed through a cut out window in the dial, as a sud-dial with small hands indicating the day / date feature or by digital readout.
Originally used to mean the size of a watch movement, this term now denotes a type of movement (men's calibre, automatic calibre, etc). When a calibre number is accompanied by the manufacturer's mark, it serves as an indication of origin.
Often used in refering to a curved or arch dial or bezel.
Unit of gold fineness (and gemstone weight). Pure gold is 24k. 18k gold is 75% pure.
The metal housing of a watch's parts. Stainless steel is the most typical metal used but also titanium, gold, silver, and platinum can be used. Less expensive watches are usually made of brass and plated with gold or silver.
Watch or other apparatus with two independent time systems: one indicates the time of the day, and the other measures brief intervals of time. Counters registering seconds, minutes and even hours can be started and stopped as desired. It is therefore possible to measure the exact duration of a phenomenon. Not to be confused with timer, the stopwatch and the chronometer.
Watch which has undergone a series of precision tests in an official institute. The requirements are very severe: a few seconds per day in the most unfavourable temperature conditions (for mechanical watches) and positions that are ordinarily encountered.
The attachment used to connect the two ends of the watch bracelet or strap around the wrist.
A watch with other functions besides time-keeping. For example, a chronograph is a watch complication. Other complications coveted by watch collectors include: minute repeater, tourbillon, perpetual calendar, or split second chronograph.
System to set the watch indicators (the hour, the minute or day) by means of the crown.
Knurled knob located on the outside of a watch case and used for winding the mainspring. It is also used for setting the hands to the right time and for correcting the correct calendar indications.
The clean cover over the watch face. Three types of crystals are commonly found in watches. Acrylic crystals, a plastic, is inexpensive and shallow scratches can be buffed out. Mineral crystals is compound of several elements that are heat treated to create unusual hardness that aids in resisting the scratches. Sapphire crystal is the most expensive and durable, approvimately three times harder than mineral crystals and twenty times harder than acrilyc crystal. A nonreflective coating on the sport styles prevent glare.
