Élémens de minéralogie docimastique ... Seconde édition. Paris, Imprimerie Royale, 1777. With an engraved frontispiece portrait of B.G. Sage by J. Beauvarlet after F.G. Colson and 2 tables (1 folding).With: (2) SAGE, Balthazar-Georges. Mémoires de chimie. Paris, Imprimerie Royale, 1778. With 1 folding table. 2 works in 3 volumes (ad. 1 in 2). 8vo. Contemporary mottled calf, gold-tooled spines with red and black labels, marbled edges, marbled endpapers.

XLVII, [1], 339; [2], 400, XLVI, [2]; VII, 262, XXXVIII pp.Two works on mineralogy and chemistry by the founder of the Paris École des Mines and the Museum of Mineralogy, the Élémens de minéralogie docimastique in its second, greatly expanded edition (first edition 1772) with a portrait of Sage and 2 plates, and the Mémoires de chimie in its first edition. Sage places "great importance on the combinative functions of acids, particularly the acid of phosphorus" (Sinkansas) and describes experiments he made on several gems.He worked closely on several projects with leading chemists Antoine Baumé and Antoine-Laurent de Lavoisier. As a teacher at the Academy and later the École des Mines he was highly regarded and esteemed by his students, who called him "the most distinguished chemist in France". By founding the École des Mines he laid the groundwork of a complete rejuvenation of the French mining industry, which was in a desolate state at the time. The Museum of Minerals housed at the École was based partly on Sage’s private collection. The present attractively bound editions in 3 volumes marks Sage's introduction into the elite of French science.Front board and first half of the leaves in volume 3 pierced with 2 small holes. Some minor wear. Otherwise in very good condition.l DSB 12, pp. 63-68; Ferguson p. 312; Sinkansas 5683; Ward & Carozzi 1944; Wilson p. 237.