gems, pearl, Ceylon, Sri Lanka, Gulf of Manaar, pearl oysters, pearl formation

Sinkankas: Previous theories on pearl formation are reviewed, including the formation of pearls in non-nacreous mollusks. The paper describes the structures and anatomy of the host, types of pearls, pearl structure, and their origin. It also includes remarks on artificial infection, the presence of foreign organisms and bodies in pearls, and pearl development up to 1901. The bibliography lists works from 1712 to 1901. Of the four illustrations, three are diagrammatic, while the fourth is a photograph showing the inner concentricity of pearl sections. This is an important paper.