I believe I have found sufficient evidence that points to a block of stone, not necessarily a coffer as stated by Idrisi, being inside the niche in the Queen's Chamber blocking the entrance to the dead-end passage.
I have been attempting to obtain illustrations online from early travelers to examine, so far without success. Does anyone know where I could source such an illustration online, preferably not paywalled?
While on the topic of the pyramids, does anyone have a theory about the insect remains found by Vyse in the relieving chamber? I was struck by it's apparent similarities to our modern-day graphite powder, and wonder if it could have been used in a similar fashion....