Tungsten! Mine is gold plated tungsten. I wore it through BMT (crawling through dirt, making beds on a metal frame that other girls rings got dented on, etc.) and theres not a spec on it. It's still super shiny and beautiful and I get compliments on it all the time. Although people still ask "why dont you wear your engagement ring?" ��
Mine: Three Keys Jewelry 2mm Tungsten... https://www.amazon.com/dp/B072LVZGXF?ref=yo_pop_ma_swf
His:Jstyle Jewelry Tungsten Rings for... https://www.amazon.com/dp/B01DKHROZ8?ref=yo_pop_ma_swf
They have tons of different styles and colors on Amazon! Some have small stones too.