China, Empire, 1 cash, cast bronze, in the name of the Qian Long emperor (ruled 1736-1795). Made in the Board of Revenue mint, Beijing. One of the most common coins the planet has ever seen - this emperor ruled for a long time, when China was peaceful and prosperous - so billions of these coins were made every year. So, despite being over 200 years old, it's still only worth a dollar or two - many coin dealers have a "Chinese cash coins - $2 each" bucket, and this would be a typical coin in such a bucket.
As for how it got there, Chinese migrants took these coins with them wherever they went, using them for trade within the Chinese community and/or for ceremonial purposes. They are still used today to make Feng Shui ornaments, though they usually use replicas rather than genuine coins for this purpose.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis