8
Oct

Washington Monument

   Posted by: dsheret759   in Uncategorized

What does the Washington Monument have to do with the gems of North Carolina?

Answer: More than anyone realizes. Attached to its top is a 5-lb. pyramid of solid aluminum made from Carolina rubies and sapphires.

That unusual fact was unknown to the historians of this region until it was discovered by the author while reviewing some metallurgical literature about the construction of the Washington Monument.

It was a well reported event in the metals world when the Monument was finally topped off in 1885 because the government decided to do it with a specially created apex cap made from aluminum. The ceremony marked the culmination of thirtyseven years of hard work – with time out for the Civil War – so that whole nation was excited about the event. But more so the metallurgists of that period because it marked the first time the unique properties of this newly discovered metal, aluminum, were being brought to the public’s attention. It was much lighter than steel yet surprisingly strong, possessed excellent corrosion resistance and was a very good conductor of electricity.

What better way to crown the top of American’s special monument to one of its greatest presidents? Choose a metal that would last forever, was a precious as silver (silver and aluminum cost the same in the late 1800′s), could be cast into the shape of a pyramid, polished to a high luster, engraved for posterity, and, perhaps more important, being a metal, it could protect the main structure of the Monument against lightning damage.

The only problem was that aluminum at that time was very difficult to produce and, therefore, very expensive. It was definitely not the familiar household metal it is today. The aluminum industry giants, ALCOA and Reynolds, were unheard of before the turn of the century.

To put the value of this metal into perspective at the time of its installation in 1884, it helps to know that its selling price was $1.00 per ounce and at that time a workman erecting the Monument had to labor for almost three months – eighty days – in order to earn enough just to pay for this little 5-lb. piece of metal sitting on its pinnacle. The cost of one ounce of aluminum, one dollar, was not only the same as an ounce of silver but it was equivalent to a full day’s wages.

One reason aluminum was so costly was because it was absolutely essential to use the highest purity aluminum oxide available which happened to be corundum, the best source of aluminum oxide known at the time. Bauxite, the ore used today in the far less costly Electrolytic Reduction Process, was not pure enough.

This is where Carolina’s unique mineral resource enters the scene. The purest corundum is in crystalline form and the best crystals were being mined commercially in the gravels, stream beds, mountain sides and soils of the Carolinas; mostly in the Cowee River Valley of Macon County, North Carolina.

Crystals of corundum are more familiar to us as sapphires and rubies. Rubies are the red ones. Any other color is called sapphire. They are the same gemstones tourists and rockhounds have been seeking at Carolina gem mines every summer for years. The famous Appalachian Star Ruby found only a few years ago by Jarvis Messer, a native of this area, is a superb example of what is still being discovered in these mountains.

Next to diamond in hardness, corundum crystals at that time were being used primarily for manufacture into “jewels” for watches and other instruments requiring precision, wear-resistant bearings. Some were fine enough to be fashioned into jewelry which was why New York City’s famous jeweler, Tiffanys, operated some of the deposits. Some were crushed and used as coatings on “emery” paper. And some were used as the “ore” for smelting that new metal, aluminum, which possessed the special properties the builders of the Washington Monument found so attractive. And to whom cost was not an issue. This, after all, was a government funded project.

To turn corundum into metallic aluminum, the crushed mineral first had to be converted chemically into aluminum chloride and then reduced with metallic sodium to form salt and metallic aluminum. Known as the Sodium Reduction Process, it was the main, reason why aluminum production was so costly. The primary reducing agent, metallic sodium, was in itself expensive, but because it was also extremely reactive – bursting into flame on exposure to air – the process was very difficult and dangerous.

The actual smelting of the corundum ore and fabrication of the aluminum apex pyramid was done by a noted metallurgist of the time, William Frishmuth, in Philadelphia, Pennsylvania at a foundry now preserved as a landmark in metallurgical history.

In late 1884, Tiffanys got into the act again, perhaps because their management provided some of the crushed gem ore from the mines they were operating in the Carolina gem fields at the time. They arranged to borrow the polished aluminum pyramid from Mr. Frishmuth for display on the floor of their Fifth Avenue store. It was literally placed on the floor” where it could serve as a publicity gimmick for the benefit of thousands of New Yorkers who delighted in being able to later say, “I stepped over the top of the Washington Monument?” Keep in mind at the time this was to be the world’s tallest manmade structure. Even today it remains the tallest free-standing masonry structure in the world.

This entry was posted on Monday, October 8th, 2012 at 3:23 pm and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.