music: 50's Chart Toppers: Name The Artist: What It Was, Was Football (Parts I & II)?

Questions

What was the name of the largest diamond ever found, presented to Edward VII by the south african govt and now set into the English Crown Jewels?

What is the Imperial unit, for use in precious metal transactions, which was authorised for retention as specialist use when other imperial units were phased out in 1999?

What is the Welcome Stranger found in 1869?

After how many years of marriage is an emerald wedding anniversary celebrated?

Which jeweller established the term sterling as the standard for silver in the United States in 1851?