A proper Victorian-era tile would have been cut by hand and be dead-flat, so a center or distributed highlight is appropriate. Modern repro tiles are machine-cut with an eased edge that contributes to an edge highlight. (And, incidentally, makes laying such tiles on floors and counter-tops a royal, screaming, freaking pain, especially when you discover this after sourcing, buying, and laying them as a repair on an existing pre-1900 tile surface. Go ahead, ask me how I know...
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