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Antimagnetic Watches

When perusing a watch retailer with a view to making a purchase it is sometimes almost impossible to understand many of the technical terms and much of the jargon that is bandied around by manufacturers and retailers in an effort to get you to buy a timepiece. An antimagnetic watch is one of the more recent terms that is being used in an attempt to secure a sale, however it is often hard to find precise definitions of exactly what an antimagnetic watch is and why it is a desirable function. To sum up antimagnetic watch as simply as possible it is a watch that will run with minimal deviation when exposed to a magnetic field. Magnetic fields are all around us in modern society; even the planet on which we live gives off an, albeit weak, magnetic field. Any field such as this can have an effect on timepieces and make them run less and less accurately as time passes. This is why an antimagnetic watch is desireable.

To give an accurate description, to be considered antimagnetic a watch must resist a magnetic field of 4,800 ampere pe meter and have a maximum deviation of 30 seconds per day. There are two main ways in which horologists construct antimagnetic watches; the first involves using a combination of alloys (invar, glcydur, nivarox and elinvar) to craft the case and the mechanical components of the timepiece making them resistant to magnetic fields. The second involves housing the entire movement and mechanism of the watch in a case that is crafted from a highly conductive material that will prevent magnetic fields from interfering with the workings inside the case.

The anti-magnetic watch was first developed in 1846 and at first consisted of a watch in which only a few of the parts inside the case were made from non magnetic metals. In the late 1800's research into new alloys was proceeding at an exciting rate and these alloys were adapted by horologists for watchmaking which allowed true antimagnetic designs to be created. In modern society the antimagnetic watch has a special place in horology; they are usually crafted with fine precision for people who work in environments that place then in or near strong magnetic fields, and such watches are widespread in engineering circles. Divers watches must also be considered antimagnetic as the deeper you dive the stronger the Earth's magnetic field is.