Number of stones
The number
of stones provided in the design of the watch.
This parameter is relevant for models that have arrows and corresponding moving parts in the "stuffing" (wheels, gears, etc.). The stones in this case are, in fact, a specific kind of bearings used to fasten rotating parts. "Stones" are made from synthetic minerals (for example, artificial sapphires). They provide slightly less friction than traditional metal bearings, and most importantly, they are more reliable and less prone to wear, which accordingly affects the durability of the entire mechanism. However, it is worth noting here that these advantages are relevant mainly for mechanical watches (see “Mechanism type”), quartz models in this sense are not so demanding on bearings.
It is believed that the more stones, the better, but here it is worth considering the functionality of the device. So, for a watch with a central second hand, 16 jewels are considered sufficient, with a side one - 17, but if there are additional functions (calendar, days of the week, etc.), this number can increase accordingly. In addition, the presence of 40 or more stones is often not so much a real necessity as a publicity stunt.
Caliber
A caliber can be described as the type of movement used in a watch. It is expensive and impractical to design a unique movement for each watch model, so most manufacturers often use the same movement in different watch models, sometimes with significantly different designs. The term "caliber" is due to the fact that initially the type of movement was designated by a number (in inch lines) corresponding to its largest size; however, today unique names or alphanumeric indices that are not directly related to sizes are widely used.
Knowing the name of the caliber on which the watch you are interested in is built, you can, if desired, find more detailed information about the mechanism and determine how its characteristics meet your requirements.
Power reserve indicatior
An indicator showing how long the watch can run without winding, changing the battery, recharging, etc. It is found in models with any type of mechanism (see the relevant paragraph). Although the
power reserve indicator is quite approximate, it still makes it easier to monitor the status of the device and reduces the risk of being left without a working watch at the wrong time.
Note that the End Of Life function (see below) in this case is not considered a power reserve indicator, although its role is generally similar.
Power reserve
The amount of time that the watch is able to operate normally without winding the spring or changing/recharging the battery (for more details, see "Power source"). Modern mechanical watches (see “Movement type”) have a standard power reserve of 40+/-5 hours. However, this parameter is usually indicated for the simplest mode of operation, without the use of additional functions such as a
chronograph(see “Functions / Capabilities” ), which also “eat up” the plant. Thus, such a watch is supposed to be wound every day, but nothing will happen if you miss the usual time and remember to wind it a few hours later than usual.
In turn, for quartz watches, the power reserve is often not indicated in the specifications. This is due to the fact that this parameter, firstly, is quite large compared to mechanical models (it would be measured in tens of days rather than hours), and secondly, it strongly depends on a number of external factors (for example, the quality of the next batteries). Therefore, it is very difficult, if not impossible, to reliably determine the power reserve in such cases.
Open case back
The presence of a case
back made of transparent material in the design of the watch, allowing you to see the mechanism.
This element does not play a practical role, but it gives the watch an original appearance. Note that the transparent cover can be combined with a Skeleton, open balance (see below) and/or a transparent case (see above) case. The key differences between these features are that Skeleton and the open balance allow you to see the movement from the front, while the transparent case can be seen through, but the movement may not be visible.
Diameter (width)
The nominal size of a watch case in diameter (for round cases) or width (for other options, see "Case Shape"). In the most miniature modern models, this size is
21 – 25 mm or even
less, among the largest there are cases of
46 – 50 mm and even
larger.
Larger watches are more convenient in the sense that the dial readings are better visible on them, and it is easier to provide various additional functions in the design. On the other hand, small watches look neater and create less discomfort directly when worn. In addition, female models (see "Gender") are traditionally made more miniature than male ones. So the choice for this indicator depends mainly on the intended specifics of the application: for example, large cases are best suited for outdoor activities and tourism, about
41 – 45 mm in size, for household wear (regardless of gender) — about
31 – 35 mm, and as an accessory to an evening dress, a small watch of
30 mm or less would be more appropriate.
Also note that the size of a compatible strap/bracelet is associated with this indicator — see "Strap Width" for details.
Thickness
The thickness of the watch case. A fairly obvious parameter; we only note that nowadays it is customary to attribute watches with a thickness of less than 7 mm to
ultra-thin models. This design has both aesthetic and quite practical meaning — a thin watch will be useful for those who wear narrow sleeves with tight-fitting cuffs.
