Yeah this is by far the most confusing part of the book so far. I've read it before and I'm looking at my old notes but I'm having difficulty with these pages (142-143), especially the paragraph on 143 that starts "hence, in the value-relation, in which the coat is the equivalent of the linen, the form of the coat counts as the form of value".

What is "The form of the coat" and what is "the form of value" here? He just introduced us to multiple different "forms of value" so which one is he referring to?

Going back to page 141 (in my copy) where marx says "If we say that, as values, commodities are simply congealed quantities of human labour, our analysis reduces them, it is true, to the level of abstract value, but does not give them a form of value distinct from their natural forms".

It seems that Marx is trying to pinpoint the "form of value" by which commodities relate. Why? Well, because their "natural form of value" is the result of concrete, useful human labor that produces qualitatively different use-values. He's looking for the qualitative substance that is in all commodities which allow them to equate quantitatively. This, for Marx, is human labor in the abstract but he makes a weird qualifier on page 142 where he asserts it isn't human labor in practice, but "coagulated" human labor and I don't know what these mean.