ATM: Measures water resistance; Stands for "atmospheres" or the amount of pressure a watch can withstand before leaking; One atmosphere is equal to 10 meters of water pressure.
Bezel: Retaining ring topping the case and securing the crystal; Sometimes incorporates unidirectional or ratcheting movements, engraved or printed chapter markers, or complications such as a tachymeter.
Chronograph: Functioning similarly to a stopwatch, a chronograph is a unique and valued complication due to its ability to measure increments of elapsed time while the watch still maintains traditional timekeeping abilities. The crown controls the analog watch while function pushers allow you to start, stop and reset the chronograph subdials.
Chronometer: High-precision timepiece that has been tested and is certified to meet precision standards; Chronometer watches often come with certificates indicating their certified status.
Complication: Any feature added to the timepiece that does not indicate hours, minutes or seconds.
COSC Certified Chronometer: Refers to timepieces that have been christened with the title of chronometer. To become a chronometer, timepieces have to pass a test conducted by the Controle Officiel Suisse des Chronometers (COSC), roughly translating to Official Swiss Chronometer Testing Institute. COSC is a prestigious Swiss government agency that certifies the accuracy and precision of timepieces in Switzerland.
Crown: Part that allows you to manipulate the watch movement for a variety of purposes such as setting the hands, changing the date, winding the mainspring, etc.
Crystal: Transparent cover on a watch face that gives view of the dial.
Deployant: Type of clasp that keeps the closing mechanism hidden, creating an uninterrupted look for your bracelet or strap.
Dual Time Zone: Timepiece that simultaneously gives time in two time zones. GMT function serves the same purpose and is used interchangeably, as it can be set to any time zone you wish.
Exhibition Case or Back: Unique complication wherein a crystal window is implemented into the back of a watch case, allowing view of the timepiece's movement.
Function Pushers: Manual controls on a case for when a movement features complications that require increased manipulation.
Greenwich Mean Time (GMT): Also referred to as Greenwich Meridian Time, the Greenwich Meridian Line is located at the Royal Observatory in Greenwich, England. It is the place from where all time zones are measured. Greenwich Mean Time is the average time that Earth takes to rotate from noon to noon. In this regard, GMT is thought of as "the world's time" and was once the basis with which every other zone set time.
Guilloche: Style of engraving that features wavy or straight lines, giving a unique effect when the timepiece is moved or shifted.
Ionic Plating: Process that produces a hardened surface that is durable and scratch-resistant; Has a black flat "stealth" finish.
Jewels: Within a movement, metal on metal contact creates wear and tear. Watchmakers use jewel bearings to reduce friction and help the delicate parts of the movement work smoothly and with great precision. Jewels help extend the movement's life. Diamonds, sapphires, rubies and garnets are the preferred materials. As a general rule, a higher number of jewels suggests a more prestigious movement.
Lugs: North and south ends of the case that attach to the strap or bracelet and often extend out from the dominant lines of the case.
Moon Phase: The lunar cycle has been a cornerstone of horology, the study of measuring time, since ancient days. Moon Phase is a complication on a timepiece that displays the various stages of the moon cycles from waxing to waning. It appears as a dial visible through an aperture which reveals the current moon phase.
Movement: Assembly making up the principal elements and mechanisms of a watch or clock; Includes the winding and setting mechanism, the mainspring, the train, the escapement and the regulating elements.
Power Reserve: Time a watch will continue running based on the movement's residual winding of its mainspring; In quartz and digital watches, this can also refer to the amount of energy left in the battery.
Push Button Dual Deployant: Similar to deployant and considered one of the most desirable and easy-to-use clasps, the push button dual deployant employs two small hidden push buttons that release the bracelet. This clasp keeps the closing mechanism hidden for an uninterrupted, seamless finish.
Repeater: Complex watch mechanism that sounds hours, quarters or minutes, or repeats them on request; Originally designed to help the wearer to tell the time in the dark.
Retrograde: Hour, minute, second or calendar hand that moves across a scale and resets to zero at the end of its cycle.
Skeletonization: Reveals the intricate symphony of moving rotors, gears and springs which power a timepiece; The open design offers an insider's view, as unnecessary metal is cut away to allow the wearer to actually see the movement's skeleton.
Swiss Made: Since the 16th century, Switzerland has been the epicenter of watch making, producing some of the industry's greatest technological advances. The Swiss put a law into effect for all timepieces baring the words "Swiss Made": First, the movement must be assembled in Switzerland. Secondly, the movement must be cased up in Switzerland. Finally, the manufacturer must carry out the timepiece's final inspection in Switzerland.
Tachymeter: Scale on a watch used to determine units per hour, such as average speed over a fixed distance, or distance based on speed; Typically located along the outer rim of a dial.
Tritium: Miniature tubes containing gaseous Tritium and layered with phosphor to power the luminous accents which can be seen for several meters in darkness. Tritium illumination requires no electrical power but must be "charged" by holding your watch close to any light source. The longer you hold it there, the longer and brighter you'll see the Tritnite.
Unidirectional Rotating Bezel: Used for tracking elapsed time. A ratchet mechanism prevents the bezel from rotating backwards. This feature is popular with divers, who rely on the elapsed time feature to prevent the diver from running out of air. The fact that the bezel cannot rotate backwards prevents the wearer from underestimating the elapsed time.
Three years after the end of World War II, the United States Mint announced intentions to replace the aging Liberty Walking half-dollar design with a brand new motif featuring a likeness of noted American inventor, philosopher, and statesman, Benjamin Franklin. Treasury Secretary John Snyder had hopes that Franklin's virtues of thrift and financial responsibility might be included among the many themes celebrated and commemorated by the coin's design. The United States Mint produced the coin until 1963, when special legislation replaced it with the Kennedy Half-Dollar.
Franklin's image on the obverse of coin was created by John R. Sinnock, who was also responsible for Franklin Roosevelt's portrait on the obverse of the 1946 dime. For the reverse of the Franklin half dollar, the Mint chose another icon from America's founding era, the Liberty Bell. However, a problem arose in the design as, according to established law, a representation of an eagle must be present on all silver coins with denominations greater than one dime. U.S. Mint sculptor, Gilroy Roberts, added a small eagle to the left of the Liberty Bell on Sinnock's design in order to comply with the requirement.
Following the tragic events of November 22, 1963, the United States Mint, at the behest of the newly sworn President Lyndon Johnson, began designing a coin for circulation that would feature the image of President John F. Kennedy. An influx of letters from the public to the Mint suggested that a significant portion of the grieving American citizenry agreed with the idea of honoring the late thirty-fifth President. The White House proposed the new coin be of half-dollar denomination and Congress swiftly passed the appropriate legislation to fast track production.
The Chief Engraver of the United States Mint at the time, Gilroy Roberts, created the now famous, commanding bust of President John F. Kennedy, which appears on the obverse of the coin. The reverse of the coin features U.S. Mint Engraver Frank Gasparro's slightly modified version of the official Presidential Seal. The new half-dollar coin became a part of the nation's circulating coinage starting in 1964 and remains so to the present. The only major change in design over the past 46 years came in 1976 when the United States celebrated its bicentennial. Just for that year, the reverse displayed an image of Independence Hall in Philadelphia and the obverse featured a dual date of 1776 - 1976. The original design resumed in 1977.
Liberty Walking Half-Dollar:
Renowned designer Adolph Weinman created the images displayed on this legendary fifty-cent piece which was struck by the United States Mint between the years 1916 and 1947. The obverse shows Lady Liberty mid-step, draped in the American flag with her right arm extended toward the sun and her left arm cradling olive branches. The reverse features a bald eagle perched on a branch.
The Liberty Walking Half-Dollar and the Mercury Dime, both designed by Adolph Weinman and introduced in 1916, each replaced a coin created by Charles Barber in their respective denominations. A new initiative championed by President Theodore Roosevelt near the turn of the century sought to have the nation's coinage redesigned and infused with a fresh sense of artistry. The movement resulted in the Barber-designed half-dollar, quarter-dollar, nickel, and dime being succeeded by the Liberty Walking Half-Dollar, Liberty Standing Quarter-Dollar, Buffalo Nickel, and Mercury Dime between the years 1913 and 1916.
Quartz: Although not as mechanically complex as other engines, the quartz movement provides the most accurate and reliable time-keeping. This type of movement typically draws power from a battery and centers around a small vibrating chip of quartz crystal. When an electrical current, supplied from a battery, is applied to a quartz crystal, the current is distorted and creates a precise resonating frequency. Watchmakers employ the subsequent frequency to measure time. Some adaptations to the traditional quartz movement include introducing rotors and power cells in an effort to maintain the accuracy of quartz while eliminating the need for a battery. Quartz movements have been used in timepieces since the 1970s and are highly accurate, dependable and affordable.