The top coin bears the inscription of a 2-cash coin from the Song Dynasty,
Xi Ning zhong bao, or "large coin of the Xi Ning emperor". The Japanese made copies of Xi Ning coins to trade with Vietnam in the 1600s, but those trade copies have the inscription "Xi Ning tong bao" instead, so I believe yours is a genuine Song Dynasty coin. "Xi Ning" was the first reign-name of Emperor Shenzong; the Xi Ning period lasted from AD 1068 to AD 1078, so your coin is almost 1000 years old. Despite its age, it is not particularly rare or valuable - the Song Dynasty was wealthy and powerful at the time, so their coins are quite common, far more common than European coins of the same vintage.
Here's a link to the Zeno.ru database page for these coins.
The bottom coin also looks Song Dynasty in appearance, though the combination of "grass script" calligraphy and the corrosion on the coin itself makes it too hard for me to read. But I'm reasonably sure the picture is upside-down.
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