Ex estate so can’t help out with any history on the item. It's made of a white metal alloy, definately not silver though. It's quite heavy set, weighs 161 grams & measures 100mm high x 55mm wide x 4mm thick. Toned with wear, scratches, marks and knocks.
This talisman came from the birthplace temple of Matsu (Ma Zu) in Meizhou Bi Ciu in local dialect, a city on a island in South China. The temple was established in AD987. Matsu is the Goddess in Chinese folk religions, on the top of the deities worshiped in South China and South Asian countries. The words on the face mean "Meizhou Ancestral Temple;" "Praying for Peace and Safety;" on the back: "pure silver." but of course as stated its a reproduction amulet / tourist piece & is not silver
