The 1941 Quadrivium Tantalum

From Grönefeld -

Courtesy of Grönefeld

This is the latest from the Grönefeld brothers Tim and Bart. This is the 1941Quadrivium in tantalum.

Quadrivium (Quad) has four complications in this one watch. Per Grönefeld:

The 1941 Quadrivium unites four of the brand’s most admired complications within a single, extraordinary watch. Developed entirely from the ground up, it features a 7.5-seconds remontoire, a one-minute flying tourbillon, central jumping seconds, and a power reserve indicator, all driven by a movement equipped with serially connected concentric twin barrels.

Courtesy of Grönefeld

This new model is available in two different versions - tantalum (above) and platinum.

Both are limited to 28 pieces.

Should you have the means and the inclination, here are the pertinents, straight from the source:

Movement

Calibre G-09

Mechanical hand-wound movement; tourbillon, remontoire, dead seconds and power reserve indicator

Movement

Diameter 32.0 mm
Thickness: 6.15 mm

Number of components

473 parts in the whole movement

Number of jewels

49 jewels, partially set in gold chatons

Power reserve

50 hours
A satellite-wheel mechanism provides a precise indication of the remaining power reserve

Barrels

Two coaxially arranged barrels connected in series toprovide a continuous and balanced energy supply

Tourbillon

One minute flying tourbillon cage made in stainless steel Durnico 

Balance wheel

Titatium free sprung variable inertia balance wheel (10.0 mm diameter)

Frequency

21.600 vibrations/hour

Balance spring

Phillips terminal overcoil curve; Geneva-style stud

Escapement

Swiss lever escapement

Main Plate

Spotted and snailed ruthenium plated brass

Bridges

Hand bevelled; stainless steel. Micro-blasted centre; circular grain on the top; relief engraved in the micro blasted surface

Dead seconds

A dedicated dead-seconds mechanism, positioned above the conventional going train, allows the escapement to operate at its natural frequency while regulating the seconds-hand to advance in precise one-second intervals

Winding-setting

Conventional winding and setting mechanism; hacking seconds at the 60 seconds position

Case and Dial

Case

1941 Design. Round, three-piece case featuring a domed sapphire crystal on the front, with anti-glare treatment on both sides. The flat sapphire crystal on the case back is also treated with anti-glare coating on both sides. The case is engraved with the serial number and secured by eight security screws

Number of components

Case: 24 parts
Dial/hands: 27 parts

Case dimensions

Diameter: 40.0 mm
Thickness: 11.3 mm

Water resistance

3 atmospheres - 30 meters - 100 feet

Crown

Engraved with “G” logo

Dial

Base dial in brass, applied stainless steel segments and white gold hour markers. Choice of 5 colors

Hands

Hours and minutes, large counter poised seconds,power-reserve. All hands are steel and heat blued

Indications

Small hours and minutes at 2 o’clock
Extra long jumping seconds hand at the center
Power reserve indicator at 10 o'clock
Visible flying tourbillon cage at 6 o’clock
Visible governor of the remontoire mechanism at 9 o'clock

Strap

Hand-sewn leather, 20mm-18mm

Buckle

Tantalum or Platinum pin buckle, engraved with Grönefeld logo. 18mm

Weight

Tantalum approximately 108 grams, including strap and buckle
Platinum approximately 120 grams, including strap and buckle

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