This is a pendant/necklace by glass artist Masahide Nakada, titled "1cm Universe." Sculpted within the glass is the Scaly-foot snail, a mysterious creature that has existed since ancient times. It's a deep-sea creature with an iron shell. I purchased it at a solo exhibition about 5 or 6 years ago for just under 30,000 yen. The display frame is also an original by Mr. Nakada. The size is about 2.5 centimeters. It's a work with a unique worldview. I've enjoyed it thoroughly, so I'd be happy to pass it on to someone who is looking for it. (I see the price has gone up a lot recently...) Thank you for looking.