IWC Portofino Automatic Steel, ref. 3513, 1997

Record summary

Catalogued by Vintage Portfolio (dealer), Vienna (stock number vp4553), this is a wristwatch by IWC, made in Switzerland, dated 1997. The Atlas places it in the Mechanical Renaissance period (1990 – 2010) of its Wristwatches collection. Materials and techniques recorded by the source: Stainless steel. Recorded dimensions: Diameter 34 mm (without crown). The record is illustrated with 6 photographs.

Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.

Catalogue description

Atlas type guide

Automatic (self-winding) watches

Self-winding watches use the wearer's motion to wind the mainspring. Abraham-Louis Perrelet and Breguet made 'perpétuelle' pocket watches with oscillating weights in the late eighteenth century, but the principle only became practical in the wristwatch. John Harwood patented a bumper automatic in 1923; Rolex's Perpetual rotor (1931) winding in one direction, and later bidirectional rotors (Eterna, Felsa Bidynator), established the modern form. Micro-rotors (Universal Genève, Buren) and peripheral rotors made automatic watches thinner.

General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.