As long as both rocks are relatively flat on the connected faces, in most cases no. A piece of paper is, what, 8 inches wide on its second shortest axis? For two “relatively” flat pieces of rock, your going to have multiple places where a small segment juts out. Those are the segments that will support all the weight of the rock, and a heavier rock will have more/thicker supporting segments. Both of those factors combined, especially on rocks as heavy as these, would lead me to expect not being able to stick a fairly large piece of paper between them. Something much thinner, like a sticky note, would be significanly easier to fit through those gaps. But a standard piece of notebook paper would not be able to fit through the gaps on my window hinges, and they are by no means sealed.
As long as both rocks are relatively flat on the connected faces, in most cases no. A piece of paper is, what, 8 inches wide on its second shortest axis? For two “relatively” flat pieces of rock, your going to have multiple places where a small segment juts out. Those are the segments that will support all the weight of the rock, and a heavier rock will have more/thicker supporting segments. Both of those factors combined, especially on rocks as heavy as these, would lead me to expect not being able to stick a fairly large piece of paper between them. Something much thinner, like a sticky note, would be significanly easier to fit through those gaps. But a standard piece of notebook paper would not be able to fit through the gaps on my window hinges, and they are by no means sealed.