gems, corundum, history.1, jade, nephrite origin, Broken Bangle

A foundational work in descriptive mineralogy by Abraham Gottlob Werner, establishing a systematic vocabulary for identifying minerals from their observable external characteristics. Werner describes such properties as color, lustre, transparency, crystal form, fracture, cleavage, hardness, specific gravity and tactile characteristics, and provides standardized terminology for recording them. Rather than being a catalogue of mineral species, the book sets out a practical method for their description and recognition, including precious stones and other minerals then commonly termed “fossils.” The work was highly influential in European mineralogy and helped establish careful macroscopic observation as a fundamental method of mineral identification before chemical analysis and crystallography became dominant.