ster·ling sil·ver ˈstərliNG ˈsilvər/ noun

silver of 92 1/2 percent purity

The hallmark used was a profile portrait of the reigning monarch’s head. The use of this mark was abolished in 1890. The date letter system was introduced in London in 1478 (elsewhere as the hallmarking system evolved). Its purpose was to establish when a piece was presented for assay or testing of the silver content.