Metal characterization - What is a "Lot" - What does the word LOT mean in Steel?

What's up guys? Michael with Michael Talks Metal back for the 148th time to do what I do best.... talk about metals.
A customer of ours received two bundles of the same item of the same heat number. He got two test reports with the same chemistry but hardness and tensile properties were different. Within spec of course, just a bit different.
What's up with that?
Apparently each bundle was a different mill shipment and mill production lot. If both bundles had been part of the same shipment from the mill, the one mill cert would have had the values from the two lots on one document. So what is a "Lot" in the world of metals?
The most universal and simple definition is that a lot is composed of material of the same chemical composition, shape, condition, and nominal cross section dimensions processed together or sequentially.
Inspections, tests, and certifications draw on the details of the production lot for requirements.

[@MAZEMIND]

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