Ductile Iron or Hardened H13
50+lbs - 3"T x 10"W   -   Bowl is approx. 7"W x 1.5"Deep
This simple shape is available in either material. The ductile version is is very tough, but will not have very much rebound. The H13 version is hardened to 53-55Rc just like our anvils, and will hold up to heavy forging.
They have been machined flat on the bottom. They have a lightly polished surface on the flat side. The flat side may have a few imperfections that should not impact the work that takes place there.
This tool is intended to be used on either side, and is a weight that is comfortable to flip while still being heavy enough to stay grounded during use.
 
Thanks to Thomas Barclay for help with the design.