The Panerai collection is largely divided into two main lines Radiomir and Luminor. There is also the Submersible diver collection which is now classified separately but was originally called the [Luminor Submersible]. The small and thin-cased Luminor Due also has its roots in the Luminor. Both Radiomir and Luminor, The two pillars of Panerai, Are named after luminous materials developed by Panerai. Watches that used radium for luminescence are called Radiomir, While those that used tritium are called Luminor.

Radiomir

Illuminating the dial with radium

Radiomir prototype coated with radium paint
© Panerai

In the early 20th century, When the dangers of radioactive materials were not yet known, Panerai developed a luminous paint by mixing radium and zinc sulfide and named it ‘Radiomir’. The name ‘Radiomir’ is believed to have originated from the Italian word for radium ‘radio’ and ‘mira’ meaning ‘aim’ or ‘sight’.

Radium emits strong radiation and boasts excellent luminescence in the dark but is a highly dangerous radioactive material. The only but fatal drawback of Radiomir was its extreme harm to the human body. After this became known, It was replaced by Luminor, Which uses tritium, A much less radioactive substance, But Panerai watches in the 1930s and 1940s still bore the ‘RADIOMIR’ title.

Wire lug

Many Radiomir watches, Including vintage pieces and current models, Have lugs that look different from modern watches. During the transition from Radiomir to Luminor, Some Radiomir models adopted a modern lug design, But when you think of ‘Radiomir’, The discreet ‘wire lug’ still stands out as a signature feature.

Thin 'wire lugs' of Ref. 3646
© Panerai

As the name suggests, Early Radiomir watches had a cushion-shaped case with thick wires soldered on, Allowing the leather strap to be threaded directly through. When Radiomir was first introduced, Wristwatches had not yet become fully established, So people had to wear watches with such imperfect wire lugs on their wrists. Panerai has brought this temporary design into the present, And by simply loosening a few screws, The lugs can be easily removed and attached in a rather smart way. If the lugs were fixed to the case as in the past, Changing straps would be quite a hassle.

The ancestor of Radiomir Ref. 3646

Ref. 3646 is the watch that set the standard for the Radiomir collection, Using Radiomir luminous material and wire lugs. With a 47mm case and, For its time, Excellent water resistance, Ref. 3646 was supplied to the Italian Navy (Regia Marina) and used by divers underwater. Although not many were made, Ref. 3646 is divided into several types depending on production period and features. Notably, ‘Type B’ uses a waterproof case supplied by Rolex and a so-called sandwich dial with a double-layer structure. Radiomir paint is applied to a copper base plate, And a plastic pin dial cut in the shape of Arabic numerals is attached on top. This creates the three-dimensional 3D dial that is characteristic of Panerai.

‘California’ dial
© Phillips

Another type, ‘Type E’, Is the California dial. This unique watch uses both Roman and Arabic numerals on the dial index. Ref. 3646 varies by type, But most were produced in small quantities. As a result, They fetch very high prices at overseas auctions.

Radiomir Tre Giorni
PAM01350

Radiomir PAM01350
© Panerai

Tributes to the origins of the collection have been ongoing. With limited case shapes and simple designs, Panerai must seek change through subtle details. For this reason, Those unfamiliar with Panerai may say that all the watches look similar. The Radiomir Tre Giorni (Radiomir Tre Giorni) PAM01350 is an homage to the ancestor Ref. 3646. It features Arabic numeral indexes and distinctive hand designs reminiscent of Ref. 3646 ‘Type B’.

Left: Radiomir Ref. 3646 ‘Type B’ / Right: PAM01350<br/>© Sotheby's, Panerai

Left: Radiomir Ref. 3646 ‘Type B’ / Right: PAM01350
© Sotheby's, Panerai

Ref. PAM01350 with a beige gradient dial was released almost simultaneously with Ref. PAM01335 (blue gradient) and PAM01334 (black gradient). Those familiar with Panerai’s history will likely be most interested in Ref. PAM01350.

The beige gradient dial itself is unique, But this color is a detail that reproduces the dial discoloration caused by the powerful radioactive material Radiomir. Of course, Now, Due to strict regulations on radioactive materials, Luminova is used as the luminous paint instead of Radiomir, But if fully charged under sunlight, You can enjoy luminous performance as strong as the original Radiomir.

It is not just the dial that shows the passage of time. The stainless steel called Patina Steel has a subtle surface gloss. It sits at the boundary between polished and matte, With a subdued shine, But the streamlined case has a gentle luster. As scratches naturally occur while wearing the watch, The case surface will look even more attractive. The only downside of Ref. PAM01350 is the caseback. Radiomir has a lower water resistance of 100m compared to the Luminor collection and features a solid caseback that visually closes the case more tightly. The wide and flat caseback improves the fit on the wrist, But the large blank space can make it feel somewhat incomplete.

Side view. Mid-case, Bezel, And crystal contrasted with the thin caseback<br/>© Fratello

Side view. Mid-case, Bezel, And crystal contrasted with the thin caseback
© Fratello

The subtitle ‘Tre Giorni’ of Ref. PAM01350 means three days in Italian. This is thanks to the caliber P.6000, Which runs for 72 hours. Although it is hand-wound, The long power reserve means you do not need to wind it frequently. The sound and feel of winding are pleasant, So it is enjoyable to wind it from time to time.

Lug design optimized for strap changes

The wire lugs, A feature of Radiomir, Are paired with a dark brown Cuoio Toscano strap. Although it looks as if it cannot be removed, By loosening the four screws visible on the caseback, The lugs can be easily detached. The wire lugs make it comfortable to wear a 45mm watch, As the short lug length means the lug-to-lug distance is not much different from a 42mm watch.

If you want to understand the origins of Panerai, I recommend experiencing it through this watch. While the more masculine Luminor with its crown guard is the representative Panerai collection, You will find that the refined basics and aged details of the Radiomir are equally captivating.