Noun
tsilaisite
(mineralogy) A triclinic mineral containing sodium, manganese, aluminium, borate, silicate, and hydroxide.
Elbaite tourmalines are allochromatic, deriving most of their color and magnetic susceptibility from schorl (which imparts iron) and tsilaisite (which imparts manganese). Source: Internet
Magnetism Opaque black schorl and yellow tsilaisite are idiochromatic tourmaline species that have high magnetic susceptibilities due to high concentrations of iron and manganese respectively. Source: Internet