Printed: October 23, 2012
Author: Natalie Angier
Written for: The New York Times
Briefly summarize the article: The article Blue through the Centuries discusses how 20,000 years ago paintings discovered were all missing the same thing, the color blue. Starting around 6,000 years ago, The Egyptians became mining a semiprecious stone called lapis. Grinding down the lapis allowed the powder to be used as pigment for coloring. Early Chinese blended Copper with other heavy metals to create blue hues. The Chinese also brewed elixirs with these elements and many emperors suffered from poisoning. Mesoamericans created the third of the ancient blue hues. They combined indigo plant extract, a mineral from clay called palygorskite, and the resin from copal. Because blue pigment was very rare and costly to make, it was associated with royalty. Later the Catholic church adopted the "color code" for saints and businesses have adopted the color to signify authority and trust.
Describe how the article relates to what you have learned in this class and/or chemistry in general: The article describes the use of copper, barium, lead, and mercury. In class, we have discussed these elements many times. We have also done experiments in lab that can help us understand and see exactly how these elements combine. All of the above mentioned elements are metals and are ionic elements. As ionic elements they are always looking to 'give away' electrons and combine easily with elements trying to gain electrons. We have also learned that these elements are typically soluble with water. This would help us explain how the compounds would be used in paints and pigments. If they were not soluble, we would be unable to create the dyeing effect that these elements produce.
Discuss/Critique how well the writer did in explaining the chemistry in the article: The author made a very basic explanation of all the minerals and compounds. By explaining things this in this manner, the general public that reads the article will not get lost in translation. The author explains what compounds and minerals are mixed together to create the blue hues but does not get anymore involved with the explanation. Doing so allows the general public the ability to understand the information the author is trying to convey. Those that understand what makes up these minerals and compounds and how they react can further understand the science behind it.
References
Angier, Natalie. "Blue through the Centuries: Sacred and Sought After." The New York Times 23 Oct. 2012, New York ed., sec. D: 3. Print.
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October 23, 2012
Blue Through the Centuries: Sacred and Sought After
By NATALIE ANGIER
However inspired they may have been by the immaculate beauty of the sky and water they saw every day, prehistoric artists had no way to render the color blue with paint. As Heinz Berke of the University of Zurich has pointed out, the famous cave paintings at Lascaux and surrounding sites, which date back some 20,000 years, are notably lacking in blue.
“Early mankind had no access to blue, because blue is not what you call an earth color,” said Dr. Berke, a chemist who has studied the history of blue pigment. “You don’t find it in the soil.” Only with the advent of mining, he said, could sources of blue pigment be extracted.
The first stable blue colorant used in the ancient world came from lapis lazuli, a semiprecious stone mined in Afghanistan beginning about 6,000 years ago. The Egyptians prized all things lapis, combining it with gold to adorn the tombs of the pharaohs, or powdering it into eye shadow for Cleopatra.
But the scarcity of the mineral drove the Egyptians to seek new blues through chemistry. By heating together limestone, sand and copper into the chemical compound calcium copper silicate, they invented the richly saturated royal-turquoise pigment called Egyptian