Specific Gravity: 3.96 to 4.01
Hardness: 9.0 (2nd only to diamonds in hardness)
Can be cleaned in ultrasonic cleaners.
Rubies and sapphires are made of aluminum oxide (corundum). The red in rubies is caused by trace amounts of chrominum. The redder the ruby, the more chrominum. Some rubies are bicolored or multicolored.
Rubies grow in crystal form and belong to the hexagonal family of shapes (before cutting and polishing).
Rubies come from Burma, Thailand, and Ceylon. In biblical times, and prehistoric time, they came from Mogok and Burma. Ancient prehistoric tools and ruby chips found by archeologists give rise to this knowledge, and the mines of Mogok are still in operation.
In 1988, a 15.97 carat ruby sold for $3,630,000.00, that's $227,300.00 per carat. High quality rubies of one carat are many times more rare than diamonds of one carat and can cost more.
0987: Coronation of Hugh Capet as King of France
1298: Edward I, King of England, crosses the Tweed at Coldstream.
1518: A drunken soldier strikes an image of the Virgin Mary, in La Rue aux Ours, Paris, and the image bleeds. The soldier was burned for sacrilege.
1608: French explorer Samuel de Champlain founded the Canadian town of Quebec.
1775: General George Washington took command of the Continental Army at Cambridge, Massachusetts.
1778: Mozart, traveling with his mother in Paris, wrote to his father and reported that his wife was ill. She was actually dead. Mozart decided to break the news gently by reporting illness first.
1806: Michael Keens exhibits the first cultivated strawberry.
1819: 1st savings bank in US (Bank of Savings in NYC) opens its doors.
1861: Pony Express arrives in SF with overland letters from New York.
1863: The three-day Civil War Battle of Gettysburg, Pennsylvania, ended in a major victory for the North as Confederate troops retreated.The Union army under command of Gen. George Meade defeated Confederate forces commanded by Gen. Robert E. Lee.
1890: Idaho became the 43rd state of the Union.
1928: The first color television transmission was accomplished by John Logie Baird in London.
1930: Congress created the US Veterans Administration.
1940: Abbott and Costello made their radio debut on NBC, replacing comedian Fred Allen for the remainder of the summer.
1944: During World War Two, Soviet forces recaptured Minsk.
1956: President Eisenhower authorizes the CIA's first U-2 flight over Russia (the first is flown the next day).
1962: Algeria became independent after 132 years of French rule.
1971: Singer Jim Morrison of The Doors died in Paris at age 27.
1986: President Reagan re-lit the Statue of Liberty's torch in New York Harbor after a $66 million restoration of the statue was completed during the 100th anniversary year of its dedication. Ships of 14 nations descended on New York harbor to pay tribute.
1989: The Supreme Court puts restraints on a woman's right to a abortion by giving the states the right to restrict abortions.
1991: Former corporate enemies Apple Computer and IBM publicly joined forces in a broad pact to swap technologies and develop new machines.
1997: In his first formal response to charges by Paula Jones of sexual harassment, President Clinton denies all allegations in her lawsuit, and asks a judge to dismiss the case.
2000: A 1970's steel observation tower that preservationists said had desecrated the battlefield of Gettysburg in Pennsylvania was demolished.