Off topic but a helpful and efficient ex-housewife did the same to my piles of linotype and #2 alloy ingots.Came home one day to find a newly clean garage with one big pile of ingots all mixed together.
There is a noticeable difference in color, hardness and sound when struck. That should be easy, but I stamp all my ingots with a set of stamps with the exact alloy of various lead so I can at least create batches that resemble a consistent alloy.
As far as the brass goes, if the primer pockets are tight and there is no separation ring they should be fine. Brass with the same headstamp should be reasonable consistent after prep. There have been group tests done of mixed brand brass and they are not so different from segregated brass as one might think.
My basic rule is don't touch or move my stuff. If it's moved I don't know where it is. I told one ex gf if she ever touched my stuff again I wouldn't let her back into the house. It's basic human respect...I don't go through her purse or hide her car keys.
