Mineral composition and gemological characteristics of jewelry-ornamental ammonites of the Republic of Adygea

Abstract

For the first time, data on the mineral composition and gemological characteristics of the jewelry-ornamental ammonites of the Republic of Adygea have been presented. Ammonites consist mainly of the calcite with inclusions of quartz, glauconite, kaolinite, aragonite, pyrite, apatite and hematite. The walls and partitions of the shells mainly lost the original aragonite composition and consist of calcite with inclusions of pyrite and apatite. Aragonite is preserved fragmentary in the walls and partitions of the shells. Calcite contains some elements-admixture, which average volumes, (wt. %), are: Mg0,62, Mn0,31 and Fe 1,26. The color and transparency of calcite is determined by the structural features of the crystals and mineral inclusions. Ammonites of the Republic of Adygea have a wide range of sizes and are associated with sediments of the lower Cretaceous. According to the decorative and technological characteristics ammonites can be used as a jewelry-ornamental material for the production of a wide range of ware.

Keywords

• ювелирно-поделочное сырьё
• ювелирные изделия
• аммониты
• кальцит
• нижнемеловые отложения