Last exhibited in 2017, it had spent much of the previous decades in storage, sitting on a back room shelf alongside other objects banned from public display.
But the artifact had a secret that was hidden from view.
The mirror from the 15th or 16th century must have hung in a temple or noble house. Recognition: Rob Deslongchamps/Cincinnati Museum of Art
The item stored in Cincinnati, Ohio was smaller than those kept in museums in Tokyo, Shanghai and New York City. It also featured a more complex style of Chinese writing. However, Sung recalled that there was something “very similar.”
Last spring, for example, she visited the museum’s storerooms, accompanied by a restoration expert.
“I asked them to shine a strong, focused light on the mirror,” Sung said in a video call from Cincinnati. “So she used her cell phone (flashlight) and it worked.”
On the wall in front of them, a texture could be seen in the reflected light–an indistinct image, but enough to warrant further investigation. After experimenting with stronger and more focused lights, the mirror finally revealed the image of a Buddha, rays of light emanating from his seated form. The inscription on the back of the mirror shows who was depicted: Amitabha, an important figure in various schools of East Asian Buddhism.

A close-up of the reflected image showing rays of light emanating from the figure of a Buddha. Recognition: Rob Deslongchamps/Cincinnati Museum of Art
“We were so excited,” Sung said.
Ongoing mystery
Before the invention of today’s glass mirrors, people from cultures around the world viewed polished bronze, from ancient Egypt to the Indus Valley. The ancient art of Chinese magic mirrors was first developed during the Han Dynasty some 2,000 years ago, although they were later made in Japan as well.
When sunlight hits the reflective surface in a certain way, a hidden image – matching the design on the back – is revealed, giving the illusion that light is shining straight through the mirror. For this reason they are known in Chinese as “transparent” or “light-penetrating” mirrors. (However, in the case of the Cincinnati Art Museum discovery, a second metal plate was likely soldered to the back, hiding the original embossed Buddha inside.)

A second bronze plate, inscribed with the name of the Amitabha Buddha, is said to have been soldered onto the back, concealing the Buddha’s image. Recognition: Rob Deslongchamps/Cincinnati Museum of Art
“No matter how much you can explain theoretically, it all depends on the master polishing the surface, which is enormously difficult,” she said. “That’s why they’re so rare.”
The museum’s mirror, about 8.5 inches in diameter, was likely used as a religious ornament and may have hung in a temple or noble household. The museum has yet to decode whether it came from China or Japan, although Sung believes it’s most likely the former.
The object was first included in the museum’s Asian art collection in 1961, although the curator believes it may have been acquired long before that. She also suspects that other institutions and collectors are in possession of magic mirrors without knowing it.
“I’ve found a lot in online auctions that have a similar design to ours, but[the auction listings]never say they’re magic mirrors,” she said, adding, “I think there might be some mirrors that people don’t like. I don’t even know they’re magical.”