What is the element formerly known as "Hydrargyrum"?

I didn't know the name but guessed based on the symbol being "Hg". Potassium is K (Kalium), Sodium is Na (Natrium) and Silver is Ag (Argentum).

Believe it or not...my dentist used to give me a little ball of mercury to play with when I was a child...who knew?

Player #57750688, I had some I kept in a tiny container. I'd pour it out and play with it. :-H