On July 7 1961, the U.S. Air Force launched a satellite called Discoverer 26 into orbit with a classified payload. On July 7, 1961, the U.S. Air Force launched a satellite called Discoverer 26 ...

Rome’s Pliny the Elder described emerald in his Natural History, published in the first century AD: “…nothing greens greener” was his verdict. He described the use of emerald by early lapidaries, who ...