This process is more expensive than mechanical slitting but could be useful for certain programs. Crucible steel, formed by bit by bit heating and cooling pure iron and carbon (usually in the form of charcoal) inside of a crucible, was created in Merv with the ninth to tenth century Advert.[38] https://pingdirapp62.directoryup.com/construcci%C3%B3n-3/euroline-steel-windows-doors