When the Future Meets the Past

A glass chalice  dating to 4th century Rome, the Lycurgus Cup is made of dichroic glass (glass which shows different colors when viewed from different directions.) It appears red when lit from behind, but green when lit from the front. It has been described as "the most spectacular glass of the period."

The cup was acquired by the British Museum in 1958, but the cause of the dichroic effect in the glass was a scientific mystery until 1990 when researchers studied the glass using an electron microscope and discovered that the chalice had been made by scattering nanoparticles of silver and gold into the molten glass. Some of these nanoparticles were ground to be less than one-thousandth the size of a grain of table salt. It is uncertain whether the artisans had perfected this technique or if it had come about by accidental contamination of the glass in the same room where silver and gold had previously been ground into a fine dust for use on other projects. It is not even known if the artisans knew what had caused this effect, or if they were as puzzled by it as modern scientists had been until recently.

Modern dichroic glass was developed by NASA researchers in the 1950s and 1960s who created it and used it to take us to the stars.