Always good to know

The coloured bezel inlays are mostly made of high-tech ceramic and extremely scratch-resistant with a hardness (according to Vickers) of 1250 HV. It is also heat and corrosion-resistant, and proffers a fine feel thanks to a high-gloss polish. The production of these ceramic bezels is very elaborate; a great deal of expertise is required to produce the different colours in a consistent quality and colour brilliance.

K1 mineral glass is a hardened mineral glass which is much harder than normal mineral glass. The glass is made by grinding and not by heating.K1 mineral glass is a hardened mineral glass which is much harder than normal mineral glass. The glass is made by grinding and not by heating.

The following comparison helps with orientation:

Vicker hardness test : sapphire - around 1900, K1 - around 700, mineral glass - around 380
Mohs hardness scale (from 0-10, the hardness of diamond is 10) : sapphire - around 9, K1 - around 6, mineral glass - around 4.

Bronze is a copper alloy and reacts in contact with oxygen (= oxidation).
A natural patina forms, which makes the bronze darker and gives each watch its own individual character. Oxidation of bronze is a natural process and not a quality defect. In order to keep the oxidation of the bronze components of a DAVOSA watch to a minimum before it is worn by the buyer, the watch is delivered in a vacuum-sealed protective cover.

We recommend to keep the watch in this cover before wearing it.
When the watch has been unpacked, the bronze parts should not come into contact with the skin in order to avoid locally increased discolouration of the surface. Bronze watches should be stored cool, dry and protected from light.

Cleaning a DAVOSA bronze watch:
We recommend not to remove the patina. It acts as a natural protective layer for the bronze. You can carefully clean the bronze parts, to remove unsightly marks: We recommend mixing salt with a little vinegar and rub in with a soft brush, then rinse with water.

Often, our customers and watch fans wonder if a certain watch is really "water resistant" and what it can be used for. Wristwatches whose original condition is resistant to water penetration up to the specified depth are referred to as "water resistant". "Water protected", however, means that the watch is resistant to splashing water or everyday (hand) washing. The DIN standard 8310 regulates whether a watch is considered "water resistant" or not. The criteria are typographic tests. Example: Under normal laboratory conditions, the watch can withstand a pressure that is 200 meters deep. This means to 20 bar or 20 ATM. The watch can be classified as a diver's watch and you can dive with it safely. Watches with 10 ATM, however, should rather be used only for swimming and snorkeling, while watches with 5 ATM are only considered "water-protected", whereby they are protected against splashing water and can be worn while bathing. If a clock is only awarded 3 ATM, you should do without bathing with this clock better. Splashing water should not be a problem.

Displaying the current phase of the moon on the dial of a mechanical watch may not sound like a big challenge. But in practice, it is complicated. The main difficulty lies in the fact that the moon does not follow an exact 24-hour rhythm. Generations of watchmakers have tried to display the moon’s orbit of 29 days, 12 hours, 44 minutes and 2.9 seconds as realistically as possible on the dial of a watch.

To adjust the moonphase function pull out the crown to position 2 as explained in the instructions provided. You can then move the moon around in a clockwise direction. The simplest way to set the moonphase dial is to wait until a full moon and then set the full moon icon at the top of the dial. However if you would like to set the moon in its exact phase immediately it is necessary to research the current phase of the moon either online or by an almanac. Remember it will take almost a month for the Moonphase dial to turn so it will be hardly noticeable on a daily basis.

In a watch with automatic winding, the centrifugal and gravitational forces are used as an energy source. A semicircular weight called the rotor or balance weight winds the spring through the arm movements of the person wearing the watch. As an automatic watch is continuously being wound, the tension spring has a sliding clutch instead of an end hook. When the watch has been wound completely, the spring descends and overstraining is circumvented.

Tritium is a colourless gas otherwise known as extra-heavy hydrogen. The name originates from the Greek word ‘tritos’ meaning third, and refers to the three components of the atom (3H). Tritium has been used for decades in all sorts of applications where constant, independent and long-lasting light sources are essential. On the dials of military watches you will often find a red, circular symbol with the notation ‘3H’ that refers to the use of tritium. In ‘civil’ watches, the abbreviation ‘T25’ denotes the same thing. In the past, luminous tritium was applied directly to the dial. Today’s watchmakers are more careful and fill the gas into fine tubes made from borosilicate glass, a highly resilient and ISO-certified glass used in chemical engineering. These Gaseous Tritium Light Sources (or GTLS) are not only exceptionally safe, they also guarantee the watch wearer at least ten years’ constant luminance – without any external energy source.

SuperLumiNova luminescent pigments are the latest patented development in the field of non-radioactive luminescent pigments. Thanks to their highly improved light storage capacity, these pigments can be used as luminescent markers on watch hands and dials. In essence, the photoluminescent pigments work like a light battery. After sufficient charging with either sunlight or artificial light, the stored light energy is discharged in the dark over a long period of time. This charging and discharging process can be repeated indefinitely and does not deteriorate or weaken over time.

The tachymeter scale on the watch face of a chronograph is used to measure the speed, e.g. of a car over a 1-km distance. The chronograph is activated when the vehicle passes the starting point and deactivated when the vehicle has reached the final point. The figure shown on the tachymeter scale corresponds to the speed in km per hour. The speed must be equal over the whole test distance.

A telemeter scale enables the calculation of the distance between an acoustic signal and its own position. Or, put more simply, it can be used to determine the proximity of a storm. To do this, the chronograph is started when lightning strikes and stopped at the first clap of thunder. It is then possible to gauge how far away the storm is by reading the telemeter scale and using the second hand as a counter. The scale is based on the well-known sonic speed value (343 m/s or 1,235 km/h), and was originally employed in a military context. It was used to determine the enemy's position via muzzle flashes and cannon fire.

The GMT function for wristwatches was originally developed in the 1950s for pilots. Their job regularly took them back and forth between different time zones, so they needed a timepiece that did not constantly have to be set to the new local time. The acronym GMT refers to Greenwich Mean Time: the official ‘world time’ until 1928. Today it has been replaced by UTC or Coordinated Universal Time, however most watchmakers still use the older terminology when referring to watches with a second time zone. How do GMT watches work? Two hour hands show the time at your place of origin and your destination simultaneously. The additional hour hand is not read via the dial with its 12 hourly markers, but rather using the exterior ring or bezel, which has a 24-hour marking. So you read the time either ‘inside’ or ‘outside’ the dial, depending on the time you wish to know.