Global Warming Potential. For instance the gas used in the...

Global Warming Potential. For instance the gas used in the Pigeon process to blanket the magnesium metal from air SF6 is compared against CO2 GWP =1. (as are all materials with GWP) Over the last 10-20 years the SF6 loss to atmosphere has dropped to 0.5kg/Mg tonne. Seems damn good, except when you learn SF6 GWP is 23,900 equiv. to 11.5 tonnes CO2/Mg tonne.

Basically means that Pidgeon process is finished.The two competing Mg processes developed in Australia certainly had better find out where they are competitive. As the product is Mg metal, price will be the only criteria. Capital cost, O&M, input energy cost and raw input cost will decide locally.
Internationally, how well each process manages the local raw input quality as well as the others above.