#gemstones
- Agates — The plural form for the mineral ahat (agate). It designates multiple pieces, specimens, or striped varieties of chalcedony. In old specialized texts or archaic museum catalogs, the term is used to classify collections of semi-precious stones characterized by diversely colored bands and alternating opacities.
- Almandine — A silicate mineral representing the most widespread and common species of the garnet group, featuring a characteristic deep red, purplish-red, reddish-brown, or black color, containing iron and aluminum. It crystallizes in the cubic system, has a vitreous luster, and high hardness (7-7.5 on the Mohs scale), with its transparent varieties utilized since antiquity as semi-precious gemstones in jewelry and opaque ones as industrial abrasives.