Adamsite-(Y) (previously IMA 1999-020), chemical formula NaY(CO<sub>3</sub>)<sub>2</sub>÷6H<sub>2</sub>O is a mineral of sodium, yttrium, carbon, oxygen, and hydrogen. It is named after Frank Dawson Adams (1859âÂÂ1942), professor of geology, McGill University. Its Mohs scale rating is 3.