Swansea General & Eye Hospital, white metal Nurses Badge

An unusual Nurses badge for the Swansea General & Eye Hospital, in that it is in white metal rather than the more common bronze or brass.I am unsure as to why but possibly a variant for long service or a management role? If anyone knows more I would love to hear from you.
The pendant design features a depiction of the hospital building within a a garter belt which bears the hospital title.Below this is a ribbon with Amica Generis Humani-Friend of the Human Race.The badge hangs from a plain pin back suspension bar brooch.Good condition.Unmarked to rear Height 45mm

Code: 53909