An electron is a subatomic particle with a negative electric charge that is equal, but opposite to, the positive charge of a proton.
Guinea (coin) The guinea was a coin of approximately one quarter ounce of gold that was minted in Great Britain between 1663 and 1814. The name came from the Guinea region in West Africa, where much of the gold used to make the coins originated. It was the first English machine-struck gold coin, originally worth one pound sterling, equal to twenty shillings, but rises in the price of gold relative to silver caused the value of the guinea to increase, at times to as high as thirty shillings. From 1717 to 1816,
From 1948-1963, the Mint produced Franklin half dollars. Once again, these were 90% silver and 10% copper. Weighing in at 12.5 grams, the current melt value of a Franklin half dollar is $8.67/each. In 1964, the Mint produced the last of their 90/10 half dollar coins. These were Kennedy half dollars, once again weighing in at 12.5 grams and having a current melt value of $8.67/each. From 1965-1970, the Mint transitioned to producing Kennedy half dollars that were 40% silver and 60% copper.