Four Special Spikes - Golden Spike National Historical Park (U.S. National Park Service)

On May 10, 1869, the Golden Spike was driven completing the first US Transcontinental Railroad at Promontory Summit, Utah It connected the Central Pacific Railroad with the Union Pacific Railroad. A short excerpt:

"The Golden Spike

San Francisco contractor David Hewes, friend of Central Pacific President Leland Stanford, was disappointed to discover no one had prepared a commerative item for the completion of the transcontinental railroad, which was scheduled to be finished on May 8, 1869. Unable to persuade anyone to finance the casting of a solid gold or silver section of rail, Hewes decided upon a more practical token. Using $400 of his own gold, he had the William T. Garatt Foundary of San Francisco cast a golden spike. The spike was 5 5/8 inches long, weighed 14.03 ounces and was made of 17.6 carat gold.

Only about $350 worth of gold, however, was used to make the actual spike. The remainder was left attached to the spike in a large sprue. After casting, the golden spike was engraved on all four sides and the top. Two sides bore the names of railroad officers and directors. Another side was engraved, “The Pacific Railroad ground broken Jan 8th 1863 and completed May 8th 1869.” The fourth side was engraved, “May God continue the unity of our Country as this Railroad unites the two great Oceans of the world. Presented David Hewes San Francisco.” The top of the spike was simply engraved, 'The Last Spike.'”