coppertalk

Adrian Forbes - guest blogger

While visiting friends and family during a trip to California over Labor Day weekend, I squeezed in a half-day visit to the Getty Center in Los Angeles.  The elevated view of the city was remarkable as well as the French Bronzes exhibit, a Renaissance to Revolution display of sculptures.  The corresponding Foundry to Finish exhibit detailed the how bronze sculptures of the period were created, including different stages of the process.

Getty Center - French Bronzes Exhibit

Coming from an analytical and engineering background, I was particularly interested in the process of crafting a large piece such as the casting of the 30-foot-high statue of Louis XIV in 1692 Paris.  The architect used the lost-wax casting technique, which is also used for creating custom jewelry.  A rough base model was formed and coated with wax, providing the artist with a workable surface for fine detail.  Upon completion of the wax exterior detail, a fire-resistant mold with an iron grid was constructed in and around the model.  The molten bronze was carefully poured into this exterior model, melting away the wax and forming a new exterior.  A sculpture of this size required an on-site foundry for pouring the material.

Getty Center - Louis XIV statue casting

What grabbed my attention was how the exterior mold was constructed to distribute the molten bronze throughout the model.  A series of arteries and capillaries (sprues) were created to reach every point of detail where it would be impossible to fill without their deployment.  It reminds me of plastic resin cast toys attached to a grid where you need to pop them out and trim the excess material.  Multiply that by one hundred.

I now have a new appreciation for how traditional bronze sculptures were created with the lost-wax technique.  I will observe pieces in parks and museums envisioning the network of sprues that may have made up the lifeline of the model.

Have you had a “Wow! So that’s how they do it.” moment with art or technology?  Chime in.  I am curious to see different perspectives.

Adrian Forbes is a software engineer and technology consultant in Ann Arbor, Michigan.

This article is not about markers made of copper. While many of the markers I found in researching it were fashioned from copper or one of its alloys, what really intrigued me was the copper storyline that emerged, the artifacts of America’s centuries-old relationship with copper.

Recently, in the course of one of those online meanderings we all succumb to now and then, I came across The Historical Marker Database (HMDB), an illustrated, searchable online catalog for people who like to share, according to the site’s tagline, “bite-size bits of local, national, and global history”.

The HMDB has hundreds of photographs, inscription transcriptions, marker locations, maps, commentaries, and links to more information. With one search, I knew I had hit pay dirt. I found fascinating remnants of copper mining and manufacturing history, told through the statues, plaques, monuments, and documentation submitted by citizen historians all over the country – and a great place to while away an afternoon.

The HMDB database can be filtered by state or country, historical period, industry, or some sixty other categories, as well as by keyword. My keyword, copper, yielded more than a few “bite-size bits” in which the semi-precious metal played a role.

These words are from a road sign in Copper Hill, New Jersey:

By 1816 copper ore was found here, and north towards Flemington. The mining craze lasted through 1865. It was never profitable, but gave Copper Hill its name. Erected 2009 by Hunterdon County Cultural And Heritage Commission. Read more…

By Ruth Danzeisen, PhD, DABT

Hemocyanin
All humans need iron for healthy red blood cells. It is an integral part of hemoglobin, and carries oxygen around our bodies, literally helping our organs and muscles to “breathe”.

Other species, however, use a different metal for this job. Crustaceans, which include crabs, lobsters, crayfish, and shrimp, use copper to bind and transport oxygen. Their “hemoglobin” is called hemocyanin, and their blood is not red, but greenish in color.

Your favorite crustaceans are not the only ones who use copper as an oxygen carrier; so does that famous extraterrestrial, Mr. Spock. Being half-Human and half-Vulcan, the USS Enterprise’s first officer uses both hemoglobin (the iron carrier) and hemocyanin (the copper carrier) to breathe, and like earth’s crustaceans, he has green blood.

Remember, the U.S. National Academy of Sciences recommends that we humans get at least 1 mg of copper per day, by eating seafood, legumes, nuts, or chocolate.

Live long and prosper!