I'm not sure about the actual percentage of mercury but yes, mercury is still an ingredient in amalgam fillings. There are still gold and full metal crowns which are made which don't contain mercury though so I don't want to imply that all metal materials in dentistry contain mercury.
thank you. I am wondering what type of filling material usually goes between a root canal and crown.
It can be different materials. You might want to ask your dentist to see what material s/he is planning to use. Most likely its a composite buildup, which is essentially a plastic.