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Astronomia Flawless Diamond Round


The Astronomia is the epitome of 21st century ultra-high-end watchmaking and a globally recognized symbol of Jacob & Co watchmaking expertise. A world-first both in the boldness of its unprecedented concept and its entirely mechanical construction, the Astronomia has gone beyond impressive horological achievements and has been regarded as an outstanding multidisciplinary engineering achievement.

The Astronomia Flawless Diamond Round represents the very essence of Astronomia: it is a cinematic sculpture animated by its four-arm movement construction that rotates and floats through a spectacular full-sapphire case. Full of unparalleled watchmaking solutions and adorned with exceptional finishing techniques, it has earned its reputation as an inimitable icon in the field of haute horlogerie.


The four arms of the Astronomia Flawless Diamond Round carry the triple-axis tourbillon timekeeping organ of the watch, the magnesium globe in hand-painted blue for a spectacular representation of Planet Earth, the exclusive Jacob-Cut® 1-carat diamond with 288 facets, and the differential-level, skeletonized time display. This four-arm assembly completes a rotation around the center of the watch in 10 minutes. Another astounding feature of the Astronomia Flawless Diamond Round is how each pair of opposing arms are perfectly calculated counterweights of one another - a testament to peerless materials engineering and watch movement design. By having equal weights on these opposing arms, its axles are relieved from strain and increased pull, as the movement takes up different orientations in space.

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The tourbillon was originally invented as a single-axis, rotating cage designed for improved timekeeping performance. The Astronomia Tourbillon brings this 224-year-old invention to breathtaking levels of modern refinement and complexity.

The triple-axis tourbillon of the Astronomia Tourbillon is at the forefront of modern watchmaking. The delicately decorated cage encapsulates the balance wheel, hairspring, escape wheel and other crucially important components. Characterized by this openworked cage, this outstanding tourbillon rotates on three axes simultaneously. It is a constellation of superbly finished components that, when assembled and fine-tuned expertly, allows the JCAM24 to keep accurate time throughout its 60-hour power reserve.

A full rotation on the 1st axis takes exactly 60 seconds, as a nod towards the traditional single-axis tourbillon. The 2nd axis of rotation requires 2.5 minutes to complete, while the 3rd axis of rotation is made possible by the 10-minute, four-arm rotating platform of the Astronomia Tourbillon. This makes for a bold new way that tourbillons can function, when engineered with cutting-edge, ultra-modern technologies and timeless horological heritage.


Astronomia Flawless Diamond Round Video


The special 288-facet Jacob-Cut diamond is a feature of the Astronomia collection. There is only one vendor in the world that can produce this patented cut and it are based in Israel. Here are the steps in its creation:

The spherical Jacob-Cut diamond starts out as a circular rough diamond. First, a rough diamond big enough must be found, and the purity, clarity, and color have to be of the highest quality both inside and out, and there can be no inclusions. If an inclusion is found in the cutting process, the gem must be replaced.

Next, the diamond is cut by machine into a round shape, near the size to the final weight of the diamond, which is usually 1 carat.

Then, the gem cutter shapes the stone by hand, cutting each individual facet (of 288). This must be done slowly and carefully, as the stone must be perfectly round and symmetrical. The danger is that the stone will become oblong. To be used in the Astronomia Collection, the Jacob-cut diamond must be completely round and weigh exactly as much as the other three satellites (time display, triple-axis tourbillon, magnesium globe).

During the process, if the gem cutter puts slightly too much pressure while adding the facets, too much of the diamond will be cut away, and the ball will end up smaller than desired. The cutting process takes at least two weeks of dedicated, painstaking work.

To make the final 1-carat, Jacob-Cut diamond with 288 facets, more than half of the initial rough diamond will be cut away.

The complexity of cutting the 288 facets by hand and making sure everything is symmetrical and the diamond is absolutely round, is what makes the Jacob & Co. diamond used in the Astronomia collection so special.

The Astronomia Flawless Diamond Round is a rare timepiece in this collection because it has two Jacob-Cut diamonds. The first is the 1-carat diamond that is being carried on one of the, which is standard on nearly all Astronomia watches. The second is a massive 2.88-carat light yellow diamond that is positioned on top of the Astronomia four-arm vertical movement.


The globe is made of blue-lacquered magnesium with white gold continents to ensure consistency in weight, as all four satellites have to weigh exactly the same. The globe rotates on itself in 30 seconds, while traveling around the dial in 10 minutes.


Astronomia Flawless Diamond Round Case is made entirely of sapphire crystal put together in three sections: case center, domed crystal and caseback, with double anti-reflective treatment


The time display sub-dial of the Astronomia Tourbillon is driven through a patented differential system that allows it to always remain always in the proper 12/6 orientation as it rotates together with the movement's four-armed platform across the front of the Astronomia. The Roman numerals on the skeletonized 18K rose gold dial are hand-engraved and filled with black lacquer, while the hand-finished hands appear in gun blue metallic.

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At A Glance

The stunning Astronomia Flawless case, completely made of sapphire

The famous Astronomia triple-axis tourbillon movement, with four satellite arms
rotating around the dial in 10 minutes

A 1-carat, 288-facet Jacob-cut diamond and magnesium globe, rotating on
themselves in 30 seconds

Time display always in the right orientation thanks to a patented differential system

A 2.2-carat light yellow Jacob-Cut diamond on top of the Astronomia movement

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Technical Specifications

Movement: Caliber: Manufacture Jacob&Co. Manual Winding JCAM24; Diameter: 40mm; Height: 17.15mm; Material: Titanium; Rose Gold Finishes; Sapphire Barrel Bridge; Components: 367; Functions: Hours and Minutes; Power Reserve: 60-Hours; Frequency: 21'600 vib/h (3 Hz); Jewels: 42; Finishing: Plate and Bridges: Hand Angled and Polished, Flank Draw, Circular Graining, Polished Sink, One Sapphire Bridge; Polished Screws; Barrel: Circular Graining; Pinions: Conical Pinions; 4 Mechanical Ball Bearing Devices; Flat Balance Spring.

System: Vertical Movement with 4 Arms, Full Revolution in 10 min around a Central Axis.

• Gravitational Triple Axis Tourbillon, 1st Cage rotating in 60 sec and 2nd Cage in 2.5 min

• Exclusive Jacob cut® Diamond (288 Facets, 1 ct.), rotating on itself in 30 sec

• Magnesium Blue Lacquered Globe, rotating on itself in 30 sec

• Hours and Minutes Dial, Patented Differential Gears System℗ allows to keep the 12/6 O'clock position

• On Top: Spherical Exclusive Jacob Cut® Yellow Diamond (~2.80 ct.)

Case: Diameter: 50mm; Height: 25.45mm; Material: Sapphire with Double Anti-Reflective Treatment; Case Back: Sapphire with Double Anti-Reflective Treatment Silver Metallization; Bows: Winding and Time-Setting via 18K White Gold Bows; Crystal: Unique Domed Sapphire with Double Anti-Reflective Treatment; Water resistance: 30m.

Dial & Hands: Dial: Titanium; Hands: Blued Jacob&Co designed hands

Strap & Clasp: Strap: Alligator; Clasp: 18K White Gold and Titanium Deployment Buckle

Limited Edition: Pièce Unique

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Flagship Boutique
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48 East 57 Street
New York, NY 10022
+1 (212) 719-5887
Jacob & Co

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