The Clifton Manual 1830 is a beautiful dress watch, hallmarked by a case in red gold, an alligator strap with curved springbars that eliminate the gap between strap and case, creating a neater appearance, and a manually-wound movement whose finish can be admired through the sapphire caseback. The dial features the unmistakable Baume & Mercier font for the numerals.
The BM12-1975M movement was designed in cooperation with the Richemont Group’s Manufacture Horlogère ValFleurier, and it has some exceptional characteristics. A power reserve of 90 hours is very useful for a manually-wound watch, not far short of 4 days.
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Owners of mechanical watches know that the precision of their timepieces seems to vary for no particular reason. Usually these variations are due to the temperature, or the position of the watch when you take it off at night. The new BM12-1975M calibre helps improve performance because it incorporates a hairspring in silicon. This material is excellent for balance springs because it is non-magnetic, but as it is a crystalline substance, it has different physical characteristics according to the orientation of the material. What Manufacture Horlogère ValFleurier have done is to laminate two layers of silicon at different orientations, binding them with silicon dioxide. The result is that the elastic and thermo-elastic properties of the two layers compensate, increasing the material’s isotropy. Timekeeping precision is improved as a result.
In addition, the balance wheel is of the inertia adjustment type, in which the rate of oscillation can be adjusted by means of weights that are part of the balance. This is a more reliable and elegant method of adjustment with respect to the more usual index-pin assembly in which the length of the hairspring is varied.
Baume & Mercier is the first Richemont brand to utilize the research involved in developing this silicon balance spring. The product has all the connotations of a prestige timepiece incorporating the latest watchmaking technology, at a competitive price considering the case material. The watch is available at 12,000 Swiss francs as from April 2017. Read more at the Baume & Mercier website.