From the discussion with Larrin and Bob Shabala:
"Yeah. So that’s a grade that, thanks to you, we had a prototype heat or an initial two heats made at Crucible, and the feedback’s been great. So, we patented it with you. We also trademarked it. So that gives us the ability to buy from both mills. And they both are getting ready to make it. So by, I think, the fourth quarter this year, we should have heats from both mills ready to go."
https://knifesteelnerds.com/2025/05/12/ ... ty-metals/
"Both mills" is referring to Erasteel and Carpenter, which are stated to be ready fourth quarter this year, so perhaps the Mules are from the "initial two heats made at Crucible"?