I was just curious whether there are differences between pencil leads between different brands given the same hardness. With fountain pen inks there appear to be a lot of variables that can go into a "plain ol black" ink. I was curious whether, for instance one brand's 0.7 mm HB lead refill behaves the same as other brand's 0.7 mm HB lead refill. I don't have much familiarity with pencil leads so my apologies if this is a naive question.
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