Phillips estimates Cartier Portico clock No. 4 at CHF 1.8m to 3.2m
The 1924 mystery clock, one of six in the series, is Lot 220 at the Geneva Watch Auction XXIV on 7 and 8 November. Its sister, No. 3, sold for CHF 3,932,000 at Phillips in May 2025.
By Carat Capital
What changed
A Portico returns to sale. Phillips will offer Cartier's Portico Mystery Clock No. 4 as Lot 220, estimated at CHF 1.8m to 3.2m. It was last offered publicly in 1996.
What it means
- If you bid in Geneva: The preview runs 4 to 7 November at the Hotel President. The sale is on 7 and 8 November.
- If you value Cartier objects: The high estimate is 18.6% below the CHF 3,932,000 that No. 3 made, a price that includes premium.
- What this is not: A result. Phillips' estimates exclude buyer's premium.
Key figures
| Estimate, Lot 220excludes buyer's premium | CHF 1.8m–3.2m |
|---|---|
| No. 3 at PhillipsMay 2025, includes premium | CHF 3,932,000 |
| Last offered publiclyGeneva, 19 November 1996 | 1996 |
| Heightweight 10.6 kg | 38.5 cm |
Source: Phillips in Association with Bacs & Russo, press release, Geneva, 27 October 2026. Estimates exclude buyer's premium.
One of six Porticos.
Six were made. Cartier made six Portico Mystery Clocks between 1923 and 1925 with clockmaker Maurice Coüet. No. 4, from 1924, is the only one with a hexagonal dial.
Built like a gate. It stands 38.5 cm high and weighs 10.6 kg. Its rock-crystal dial hangs between two square rock-crystal columns, under an arch that hides the movement.
| Detail | No. 4 | No. 3 |
|---|---|---|
| Made | 1924 | 1924 |
| Dial | Six sides | 12 sides |
| Columns | Square, rock crystal | Square, rose quartz |
| Last at auction | Offered 1996 | Sold May 2025 |
| Price | Estimate CHF 1.8m–3.2m | Sold CHF 3,932,000 |
Phillips' estimates exclude buyer's premium; its prices achieved include hammer plus premium, the release says.
Provenance runs through the family.
Alain Cartier owned it. The clock belonged to Alain Cartier, grandson of Louis Cartier, Phillips says. It was last offered at The Magical Art of Cartier in Geneva on 19 November 1996.
A maharajah, reputedly. Phillips says the clock reputedly belonged to the Maharajah of Nawanagar. It comes with a Cartier certificate of authenticity dated 2002.
No. 3 set the mark.
The sister sold. Its sister, made the same year, sold at Phillips' Geneva Watch Auction XXI in May 2025 for CHF 3,932,000. That price includes buyer's premium; the estimate for this clock does not.
What to watch
- 4 to 7 November 2026The Geneva preview at the Hotel President. The test: whether Phillips changes the estimate before the sale.
- 7 and 8 November 2026The Geneva Watch Auction XXIV. The test: whether Lot 220 sells, and how it compares with No. 3's CHF 3,932,000.
The story so far
Go deeper
What would change this call
No sale, or a hammer below CHF 1.8m, would put No. 4 under the house's own estimate despite No. 3's result in May 2025.
How an estimate is read
Phillips' estimates exclude buyer's premium, and its prices achieved include hammer plus premium, the release says. An estimate and a result are not like for like.
Method
Phillips in Association with Bacs & Russo, 'Phillips to offer Cartier Portico Mystery Clock No. 4 at the Geneva Watch Auction: XXIV', dateline 'GENEVA – 27 OCTOBER 2026'. PDF fetched by the Editor at 14:06 EST 3 November 2026 with tools/door.py, 200, 326,174 bytes (newsroom/sources/2026-11-03/desk/portico.pdf, the same count as the Bureau's), text layer extracted with pypdf, 3 pages, 9,556 characters (portico.txt). Grep of the extracted text: '1,800,000' 1, '3,200,000' 1, '3,932,000' 1, '38.5' 1, '10.6' 1, 'Lot 220' 1, '7 & 8 November' 3, '1996' 3; read in their sentences: 'one of only six examples of the series created between 1923 and 1925', 'the only Portico known with a hexagonal dial', 'Lot 220 with an estimate of CHF 1,800,000–3,200,000', 'Formerly the property of Alain Cartier – grandson of Louis Cartier', 'last offered publicly at The Magical Art of Cartier in Geneva on 19 November 1996', 'Reputedly, the clock had once belonged to the Maharajah of Nawanagar', 'Cartier Certificate of Authenticity dated 2002', 'Preview: 4–7 November 2026', 'Hotel President', 'the only two with square rather than round columns', 'rose-quartz columns and 12-sided carved rock-crystal dial', 'Estimates do not include buyer's premium; prices achieved include the hammer price plus buyer's premium'. Arithmetic, ours: 3,200,000 / 3,932,000 = 0.814 -> 81.4% of No. 3's price -> 18.6% below. No dollar figure: the release prices in francs and no rate was read. Not used: JCK's estimate of CHF 1.8m to 3.6m and its 'up to $3.9M' headline (2 November), and a Rapaport 'USD 4M' headline; neither is in the release. ARCHIVE, by entity: 'Portico' 0 hits, 'Geneva Watch Auction' 4 hits (none names this sale or lot), 'Cartier' with 'clock' 1 hit, a Patek piece of 17 October (archive-hits.py, the Editor, 3 November). Ours: none on this lot | new: Lot 220, sale 7 and 8 November: NEW. Filed under watches for the clock and the sale; the auctions desk filed the same release.