Okay, so when I first saw this headline, I was confused. I somehow thought a Magic Mirror was one of those incredibly fancy pieces of at-home gym equipment. I clicked mostly to resolve my confusion but was drawn into the story right away. For those not in the know (like myself) Magic Mirrors date back to the Han Dynasty in China wherein polished bronze, not glass, was used to make mirrors. CNN describes the complex and difficult process here:
To create the mysterious effect, artisans began by casting images, words or patterns onto one side of a bronze plate. Scientists believe they then scratched and scraped the plain surface on the other side, before polishing it until it became reflective like a conventional mirror. Because the plate was of varying thickness, due to the embossed design, the process created very slight changes in curvature on the seemingly blank mirrored side. A mercury-based substance was then used to make additional surface stresses that were invisible to the naked eye but matched the elaborate patterns on the back, according to an article in the UNESCO Courier journal.
When sunlight hits the reflective surface in a certain way, a hidden image — matching the design on the back — would be revealed, giving the illusion that light was passing right through the mirror. For this reason, they are known in Chinese as “transparent” or “light-penetration” mirrors. (In the case of the Cincinnati Art Museum’s discovery, however, a second metal plate was likely soldered onto the back, leaving the original embossed Buddha concealed inside.)
After reading about how these mirrors were created, and how so much of the final product revolved around the maker’s specific techniques, all of which are still not fully understood, it was no surprise that finding one in storage at the Cincinnati Art Museum was so exciting. If you’re in the area, go check it out!