Although there are dozens of different types of gems, among the best known and most important are diamond, ruby and sapphire, emerald and other gem forms of the mineral beryl, chrysoberyl, tanzanite, tsavorite, topaz and jade.

So I handed out lyrics by Allan Sherman, the shticky 1960s parody writer who my father revered and channeled to the end.

This is a product of lime and nitric acid.

I: I think there may be something living in there. I think there may be something alive. Withnail: What d'you mean? A rat? I: It's possible. It's possible. Withnail: Then the fucker will rue the day!