"I am inreceipt of information indicating that what is going to be deposited in Silbury is a stone that was removed during the digging of the original tunnels.

So long as that is ALL that is going in this may already be resolved. But an open eye would probably still be a good idea."

Well, an invitation to Pagans, PLUS this stone..... sort of opens the field for other things to be suggested - by others....

It all sounds a bit unclear to me. What stone? Why? Will it have a plaque attached? Bear in mind, one of the guiding principles that the Silbury project team set itself was "new work must be distinguishable". Sticking an old stone back in, in a different spot, might seem a small matter but it does transgress the principle and if it can be done in that instance it could be done in others.

So "Nothing but chalk" (and it would need to be "marked" with inert glass beads or whatever) seems a nice safe campaign call to me.