A method to manufacture a hairspring of a timepiece movement, which includes: producing a malleable elongated element in a form of under a fiber or ribbon form, from a first heated material capable of guiding light; conforming the malleable elongated element in order to achieve into a spiral form; and handling processing the spiral form thus created in order to obtain a hairspring for providing both a mechanical oscillating function in a balance wheel and a light guiding guide lighting function arranged for in situ adjusting of a mechanical performance of said hairspring. The conforming includes coiling the malleable elongated element around a rotating mobile conformation tool, and receiving the malleable elongated element in a guiding channel within a guiding mechanism and guiding the received malleable elongated element via mobile equipment turning on an inner periphery of the guiding mechanism.

A spiral timepiece spring with a two-phase structure, made of a niobium and titanium alloy, and method for manufacturing this spring, including producing a binary alloy containing niobium and titanium, with niobium: the remainder to 100%; titanium between 45.0% and 48.0% by mass of the total, traces of components among O, H, C, Fe, Ta, N, Ni, Si, Cu, Al, of between 0 and 1600 ppm by mass of the total individually, and less than 0.3% by mass combined; applying deformations alternated with heat treatments until a two-phase microstructure is obtained including a solid solution of niobium with -phase titanium and a solid solution of niobium with -phase titanium, the -phase titanium content being greater than 10% by volume, with an elastic limit higher than 1000 MPa, and a modulus of elasticity higher than 60 GPa and less than 80 GPa; wire drawing to obtain wire able to be calendered; calendering or winding.

Method for fabrication of an antiferromagnetic and temperature compensated timepiece balance spring, including the steps of: selecting an amagnetic iron-chromium-nickel-manganese-beryllium compensating alloy, comprising, by mass percent, between and including: from 21.0% to 25.0% of manganese, from 9.0% to 13.0% of nickel, from 6.0% to 15.0% of chromium, from 0.2% to 2.0% of beryllium, the remainder iron, the total of nickel and manganese being higher than or equal to 33.0%, working the alloy to obtain a blank, shaping the blank by casting and/or forging and/or wire drawing and/or rolling and/or drawing, to obtain a blank of spring wire; winding the wire on a winder to obtain a balance spring, subjecting the spiral spring to at least a heat setting treatment, by annealing at a temperature comprised between 540 C. and 650 C., for a duration of 30 to 200 minutes, to obtain a balance spring.

A balance-spring intended to equip a balance of an horological movement, comprising a core made of NbTi made from an alloy consisting of: niobium: balance to 100% by weight, titanium: between 5 and 95% by weight, traces of elements chosen from the group consisting of O, H, C, Fe, Ta, N, Ni, Si, Cu, Al, each of said elements being present in a quantity between 0 and 1600 ppm by weight, the total quantity formed by all of said elements being between 0% and 0.3% by weight, wherein the core made of NbTi is coated with a layer of niobium, said layer of niobium having a thickness between 20 nm and 10 ?m.

A compensating balance spring for a thermally compensated sprung balance resonator including a core formed from at least one non-metallic material. The core is entirely coated with a layer which is moisture proof to render the balance spring less sensitive to climatic variations. The compensating balance spring can be applied to timepieces.

A compensating balance spring for a thermally compensated sprung balance resonator including a core formed from at least one non-metallic material. The core is partially coated with at least one layer which is moisture proof to render the balance spring less sensitive to climatic variations.

A balance wheel including a rim connected to a hub with at least one arm, wherein the balance wheel includes an adjustable auxiliary temperature compensation system mounted in the space defined by the rim to allow adjustable temperature compensation of the balance wheel.

A method for manufacturing a horological mobile (10) including: depositing a first thin layer (11) with a first material including at least nickel, the periphery of which defines the contour of the geometry of the horological mobile (10); depositing an intermediate layer (12), with a second material including at least nickel and phosphorus, so as to cover a face of the first thin layer (11), the periphery of which corresponds to that of the geometric shape of the first thin layer (11); depositing a second thin layer (13) with the first material, so as to cover a face of the intermediate layer (12), the periphery of which corresponds to that of the geometric shape of the first thin layer (11), wherein the first and the second thin layer (11, 13) are poorer in phosphorus than the intermediate layer (12), or do not contain any phosphorus.

A torque-restoring element for an oscillator for a mechanical timepiece and having an oscillator frequency, said torque restoring element comprising a spiral spring body having a number N turnings with an inner terminal end for engagement with a rotational inertial element via a collet, and an outer terminal for engagement with a stationary cock element, and having a width, a height and a total arc length; wherein the spiral spring body includes a core formed from mono-crystalline silicon wafer oriented along the crystallographic axis <110>; and wherein the spiral spring body includes at least one peripheral coating of a material having a thermal elastic constant different from that of the core of the spiral spring body so as to maintain the oscillator frequency an oscillator including the torque-restoring element substantially insensitive to variations of ambient temperature.

Method for fabrication of an antiferromagnetic and temperature compensated timepiece balance spring, including the steps of: selecting an amagnetic iron-chromium-nickel-manganese-beryllium compensating alloy, comprising, by mass percent, between and including: from 21.0% to 25.0% of manganese, from 9.0% to 13.0% of nickel, from 6.0% to 15.0% of chromium, from 0.2% to 2.0% of beryllium, the remainder iron, the total of nickel and manganese being higher than or equal to 33.0%, working the alloy to obtain a blank, shaping the blank by casting and/or forging and/or wire drawing and/or rolling and/or drawing, to obtain a blank of spring wire; winding the wire on a winder to obtain a balance spring, subjecting the spiral spring to at least a heat setting treatment, by annealing at a temperature comprised between 540 C. and 650 C., for a duration of 30 to 200 minutes, to obtain a balance spring.