Why and how would it have Titanium?
Because these metals come from the ground and aren't distributed in easy to mine pockets of pure elements. Those are called "trace elements" and are an accepted result of refining on the level that existed for 1948 cents or even today, depending on the standards for the product. Even if no tin or titanium was shown to exist there (or lead, cadmium & mercury), the percentages of copper and zinc are close enough to the desired proportion to give a proper weight if the planchet was properly sized to begin with. As it is, a proper metallic composition combined with a low weight and lack of major environmental damage means that the planchet was undersized when struck.
I don't get this whole thread
There's nothing to get beyond what you already described.
Tantum religio potuit suadere malorum.
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