Rado Diastar Lux 21 Jewels Ref. 636.0013.3 (Vintage)
Dress Watch / Tool Watch Hybrid · Rado (part of ASUAG during this era, now Swatch Group). Known as the 'Master of Materials' for pioneering scratchproof hardmetal cases.
Period: Space Age / Funk Era (1970s). Defined by the tonneau 'cushion' case, faceted crystal, and champagne eccentric dial which was typical of the mid-70s Rado design language.
Type
Dress Watch / Tool Watch Hybrid
Brand
Rado (part of ASUAG during this era, now Swatch Group). Known as the 'Master of Materials' for pioneering scratchproof hardmetal cases.
Movement
Automatic, likely ETA 2836 or 2789 caliber, 21,600 bph frequency, approx. 40-hour power reserve, 21 jewels featuring day-date complication.
Dimensions
35mm diameter, 12mm thickness, 42mm lug-to-lug, 18mm lug width. Wears larger due to the slab-sided tungsten top shell.
Description
The Rado Diastar Lux is an icon of 1970s industrial design. This 'Lux' variant features a revolutionary tungsten carbide case that remains virtually scratch-free for decades. The highlight is the prismatic faceted crystal which plays with light like a gemstone, reflecting the gold-tone dial indices in a kaleidoscope effect. It represents an era when Swiss watchmaking leaned into 'Space Age' aesthetics and exotic materials to survive the Quartz Revolution.
Key Features
Tungsten Carbide 'Hardmetal' case, 9-facet prismatic crystal, rotating anchor logo (which moves with wrist gravity), and distinct 1970s slab case geometry.
Dial Description
Champagne/Gold sunburst dial with an 'ice-facet' prismatic pattern; applied block indices, baton hands with lume strips, day-date window at 3 o'clock, and the signature Rado rotating anchor logo at 12.
Case Material
Tungsten Carbide (Scratchproof) top shell with polished finish and a gold-plated bezel ring; stainless steel inner chassis and caseback.
Crystal Type
Faceted Sapphire Crystal with '9-facet' diamond cut. Known for its 'Lux' prismatic light refraction. Condition appears good with minor dust.
Bezel Details
Fixed smooth gold-tone inner bezel integrated into the tungsten carbide outer case protective shell.
Crown & Pushers
Push-pull crown at 3 o'clock (partially recessed); additional recessed quick-set pusher at 4 o'clock for the date/day function common in 1970s ETA movements.
Bracelet or Strap
Stainless steel H-link style 'Novavit' type bracelet with a folding clasp; brushed and polished finish combinations.
Caseback Details
Screw-down solid stainless steel caseback featuring the Rado 'Seahorse' trio logo and water-sealed engravings.
Movement Type
Automatic, likely ETA 2836 or 2789 caliber, 21,600 bph frequency, approx. 40-hour power reserve, 21 jewels featuring day-date complication.
Water Resistance
Originally rated for 30-50m (splash resistant); given the age of the gaskets, it should be considered non-water resistant until pressure tested by a professional.
Origin & Provenance
Swiss Made. Manufactured in Lengnau, Switzerland. Uses an outsourced but high-grade adjusted ETA movement.
Age Estimate
Circa 1974-1979. Identified by the 'T Swiss Made T' tritium marking and the specific faceted crystal style popular in that decade.
Cultural Significance
Hugely popular in Far East and Middle Eastern markets during the 70s as a symbol of status and durability. It pioneered the use of non-steel materials in luxury watchmaking long before ceramic became mainstream.
Condition Notes
Case appears in 'Very Good' condition (the benefit of tungsten). Crystal facets are sharp. Dial shows slight aging at the edges. Bracelet shows moderate 'stretch' or slack between links. Overall Grade: Very Good.
Value Estimate
$400 - $850 USD. Factors include crystal clarity (replacements are expensive) and the presence of the original 'NSA' or Rado-signed bracelet.
Care & Maintenance
Service every 5-7 years. Avoid dropping on hard surfaces like tile—while tungsten is scratchproof, it is brittle and can shatter. Check gaskets regularly to ensure water resistance is maintained.
Similar Watches
Omega Constellation 'C-Shape', Rolex Oysterquartz, Mido Commander. Rado remains unique for its use of Tungsten Carbide compared to the steel used by competitors.
Interesting Facts
The Diastar was marketed as the world's first 'scratchproof' watch in 1962. The rotating anchor at 12 o'clock is actually mounted on a ruby jewel and serves as a visual indicator of the automatic winding health; if it spins freely, the movement is generally clean.