Silver Amalgam. There have been many modifications of amalgam over the years. Most of these have been designed to improve working properties as well as durability. But at the most basic level its changes are surprisingly few.
No. Amalgam technology is "mature", that is, it is as good as it gets. I have been using the same brand for over 30 years. It lasts a very long time, unlike composites, which are plastic resins and tend to wear out when used in back teeth. Composite technology improves every few years, but the newer materials have no long-term track record. Patients are part of the experimental pool.