First described in 1941 for an occurrence in mine dumps of the Victoria Segunda mine Cerros Pintados, Iquique province, Tarapacá Region, Chile.
Cadwaladerite is named for Charles Meigs Biddle Cadwalader, president of the Academy of Natural Sciences, (1885-1959).
Lesukite
IMA 18-H: Redefinition of cadwaladerite and discreditation of lesukite
Proposal 18-H is accepted, demonstrating that cadwaladerite and lesukite are the same mineral species. Because cadwaladerite has historical precedence, it is recognized as a valid mineral species, whereas lesukite is discredited. Furthermore, the formula of cadwaladerite is redefined as Al5(H2O)3(OH)12·n(Cl,H2O).
