A little-known icon from the golden age of Japanese quartz watches! Released in the late 1970s (perhaps 1975), this remarkable Ricoh Riquartz, model 591007, is one of the most unconventional watches produced by the Japanese watch industry during the quartz revolution. While Seiko monopolized the public’s attention following the launch of the Astron in 1969, Ricoh quietly developed its own line of high-end electronic movements under the “Riquartz” brand. These models were intended for a discerning clientele seeking precision, reliability, and exclusive design. This reference 591007 is now known among collectors as the “Silver Nugget,” due to its spectacular textured case reminiscent of a raw silver nugget shaped by nature. Particularly rare on the international market, this version combines a 925 sterling silver case, an exquisitely refined “frozen” silver-toned textured dial, and a Ricoh-manufactured quartz movement with 9 jewels. The reference number 591007 is also considered by many specialized collectors to be a nod to the model’s launch year: 1975, a period during which Ricoh sought to demonstrate its technological expertise in the face of major Japanese quartz manufacturers. Today, this model remains one of the most sought-after vintage Ricoh watches among enthusiasts of niche Japanese timepieces. Technical Specifications * Brand: Ricoh * Model: Riquartz Silver Nugget * Reference: 591007 * Year: 1975 (approximate) * Country of Manufacture: Japan * Movement: Ricoh Riquartz Caliber 590 * Quartz * 9 jewels * Quick-set date function * Case: 925 sterling silver * Case back: Stainless steel * Crystal: Mineral * Diameter: 37 mm excluding crown * Lug width: 18 mm * Non-original brown leather strap - Original Ricoh solid silver buckle * Water resistance: Not guaranteed due to the watch’s age ⸻ Condition This watch is in exceptional condition for a model that is approximately 50 years old. Dial * Remarkable condition * Original texture perfectly preserved * No notable defects observed Hands * Excellent condition Crystal * Very good overall condition 925 sterling silver case * Exceptional condition * Hammered relief perfectly preserved * Very minimal wear for its age * Appearance significantly superior to examples typically found on the market Movement * Ricoh Riquartz Cal. 590 movement * Functioning verified * Date change operational ⸻ Why this watch is rare * Genuine 925 sterling silver case * Limited Japanese production * Ricoh in-house movement * Spectacular textured dial * Iconic “Silver Nugget” design * Model rarely offered for sale * A sought-after piece among collectors of vintage Japanese watches ⸻ What’s Included * Ricoh Riquartz 591007 Silver Nugget * Brown leather strap * Alternative presentation box