They have a hardness rating of 7.5 to 8, so diamonds and sapphires would scratch ... They may not react well to sudden ...

Besides yellow, the stone comes in a range of hues, including blue, pink, violet, brown and orange. Topaz is primarily mined in Brazil and northwestern Pakistan, the Geological Institute of ...

Victims suffered from jaundice, high fever and black vomit. For more than two hundred years, yellow fever — as the disease became known — attacked numerous American cities, usually in severe ...

Yellow fever appeared in the U.S. in the late 17th century. The deadly virus continued to strike cities, mostly eastern seaports and Gulf Coast cities, for the next two hundred years, killing ...

Put a known volume of water into a boiling tube. Add soap solution, one drop at a time, and shake the mixture for 10 seconds. Record the number of drops of soap needed to make a lather. The ...

Mines at White Cliffs began producing in 1890. 5. D Topaz is a very hard gemstone, with a Mohs hardness of 8, but it can be split with a single blow, a trait it shares with diamond. Diamond is ...

Sodium carbonate, Na 2 CO 3, is also known as washing soda. It can soften water that has temporary hardness and it can soften water that has permanent hardness. It is an inexpensive method of ...

The Cambridge Topaz Reference Bible echoes the beauty and clarity of the classic Bible settings of the past. It answers the call for a larger format reference Bible of the highest quality, available ...

The Cambridge KJV Topaz Reference Edition echoes the beauty and clarity of the classic Bible settings of yesteryear. Traditionally named after a precious stone, this large-format setting has a ...

A bankruptcy judge ruled that failed trucker Yellow can’t escape its pension withdrawal liability, dealing a blow to other ...