Composition
For silver crowns, the grade of silver adhered to the long-standing standard (established in the 12th century by Henry II) – the Sterling Silver standard of 92.5% silver and 7.5% copper. This was a harder-wearing alloy, yet it was still a rather high grade of silver. It went some way towards discouraging the practice of "clipping", though this practice was further discouraged and largely eliminated with the introduction of the milled edge seen on coins today.
In a debasement process which took effect in 1920, the silver content of all British coins was reduced from 92.5% to 50%, with a portion of the remainder consisting of manganese, which caused the coins to tarnish to a very dark colour after they had been in circulation for a significant period. Silver was eliminated altogether in 1947, with the move to a composition of cupro-nickel – except for proof issues, which returned to the pre-1920 92.5% silver composition.
Since standardisation of the UK's silver coinage in 1816 (UK Coinage Reform 1816), a crown has, as a general rule, had a diameter of 38.61 mm, and weighed 28.276g.
Read more about this topic: Crown (British Coin)
Famous quotes containing the word composition:
“Modern Western thought will pass into history and be incorporated in it, will have its influence and its place, just as our body will pass into the composition of grass, of sheep, of cutlets, and of men. We do not like that kind of immortality, but what is to be done about it?”
—Alexander Herzen (1812–1870)
“There was not a grain of poetry in the whole composition of Lord Fawn, and poetry was what her very soul craved;Mpoetry, together with houses, champagne, jewels, and admiration.”
—Anthony Trollope (1815–1882)
“There is singularly nothing that makes a difference a difference in beginning and in the middle and in ending except that each generation has something different at which they are all looking. By this I mean so simply that anybody knows it that composition is the difference which makes each and all of them then different from other generations and this is what makes everything different otherwise they are all alike and everybody knows it because everybody says it.”
—Gertrude Stein (1874–1946)