The Arnold & Son HM Steel Pietersite presents a refined interpretation of the ultra-thin luxury dress watch, combining the "Tempest stone" with precision mechanical watchmaking. Its striking pietersite dial, known for its fluid, storm-like patterns, creates a constantly shifting visual landscape, making each timepiece entirely unique. Inspired by the rugged Cornish coastline and the legacy of English horology, this elegant 39.5 mm watch captures the spirit of exploration and resilience. Shown here in stainless steel, this limited edition mechanical watch balances heritage design with contemporary sophistication, offering a distinctive option for those seeking a unique Swiss dress watch with character.

A limited edition of 18 pieces.

Pre-order now for livery in May 2026

Ref. 1LCDS.Z02A.C1506S

Beneath its expressive dial, the HM Pietersite is powered by the ultra-thin in-house calibre A&S1001, a hand-wound mechanical movement engineered for performance and finesse. Measuring just 2.70 mm in height, this finely finished movement delivers an impressive 90-hour power reserve, positioning it among the most desirable long power reserve dress watches in its class. Visible through the sapphire case back, traditional haute horlogerie finishing techniques highlight the brand’s dedication to craftsmanship. With its slim 7.82 mm profile, refined proportions, and alligator leather strap, this luxury mechanical watch transitions effortlessly from formal occasions to everyday wear, offering enduring style with exceptional watchmaking pedigree.

TECHNICAL SPECIFICATIONS
Calibre
- A&S1001
- Mechanical manual winding
Functions
Hours & minutes
Calibre Measurements
- 30 mm diameter
- 2.70 mm thickness
Power Reserve
90 hours
Frequency
3 Hz / 21'600 vph
Finishes
- Main plate: rhodium-plated and circular-grained
- Bridges: chamfered, radiating Côtes de Genève
- Wheels: snail-finished
- Screws: blued, heads polished and chamfered
Case
Stainless steel
Measurements
- 39.5 mm diameter
- 7.82 mm thickness
Crystal
Domed sapphire with a double-sided anti-reflective coating
Caseback
Sapphire with an anti-reflective coating
Dial
Namibian pietersite
Water Resistance
3 atm / 30 meters
Strap
- Ink blue alligator leather
- Stainless steel pin

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