“metallurgical Works” By Johann Christian Orschall—a Rare 1761 Edition

A rare 1761 edition of *Oeuvres Métallurgiques* by Johann Christian Orschall, mining inspector for the Landgrave of Hesse-Kassel. French edition translated from German by Baron d’Holbach—published in Paris by Jean Thomas Hérissant in 1761.
A very interesting collection of the author’s scattered German works on mining, metallurgy, and metallurgical chemistry, translated by Baron d’Holbach. It includes detailed descriptions of three alchemical processes for producing large quantities of gold. Despite its alchemical overtones, the work provides valuable information on extractive metallurgy.
Orschall remains famous for his description of a process for producing fake rubies by dyeing glass, as described in this book.
It also covers the operations required in copper and lead mines, how to process gold and silver ores, and how to extract sulfur, as well as numerous experiments and specific processes.
The book consists of 394 pages. On page 110, there is a fold-out engraved plate.
Hardcover. Very good condition.