A handwritten, double-sided chart dated June 1929 , drawn on a small piece of stiff cardboard. It presents the technical specifications and conditions applied to the crushing, sieving, burning , and melting of materials containing precious metals: gold, silver, platinum, filings, sweepings, dental wire, photographic ashes, etc. Written in ink on graph paper glued to cardboard, this document likely served a recycling or refining workshop, probably in Paris, specializing in the extraction of precious metals from industrial or jewelry waste. A valuable record of the professional practices of the time, at the crossroads of applied chemistry, the circular economy, and goldsmithing.
✦ Origin: France ✦ Estimated period: June 1929 ✦ Dimensions: 21 × 18 cm ✦ Material: Stiff cardboard, handwritten graph paper ✦ Contents: Precious metals processing schedules ✦ Condition: Very good overall condition, edges slightly worn, ink stable and legible on both sides
Rare reference document on industrial methods of refining precious metals – ideal for a specialized collection in goldsmithing, antique chemistry or raw materials economics.
