The two I have both have welded steel working bits.  I had one in the 
early '70's that was an old spring, repurposed by a blacksmith named 
Einar Oin, from  Rapid City.  I later bought my first anvil, a Swedish 
steel one, swage block and a few tongs from him.  He taught me how to 
harden and temper mining picks.  The side of the anvil was the testing 
ground.  Little square holes all over from checking the hardness and 
toughness, by hitting the side.  There were a few of the holes that had 
mill pick tips still in them......those failed and were reground a tad, 
then tempered a little more.  Found a few hundred tongs at old mining 
sites in the Hills.  One, in the remains of the ghost town Spokane, had 
a hundred all by itself..  The calendar was on the wall, 1941......mine 
closed due to war and never reopened.
When they were building all the Minuteman silos around that part of the 
country Einar had the contract to sharpen all the air hammer chisels 
that they cleaned up the cast concrete silos with.  By the TON....  I 
sharpened my share of those for him when going to college at the School 
of Mines.


God bless.