A few mistakes in the article of which one is that the stone is Dolomite. Dolerite shurely?
IMHO the "Healing" theory may possibly have a grain of truth in it (think Lourdes whether you believe or not) but the presence of the chips may have
much more mundane explanations.

The bluestones were undoubtedly shaped/modified on site accounting for the waste products.
At one time it was possible to hire a hammer and chisel at the entrance for the purpose of hacking off souvenirs.
Possible frost weathering etc etc.

I would have thought that the Astronomer Priests/Beaker People/Welsh/Druids/Martians/(add builder of choice), would have been really, really pissed off if the hoi polloi turned up and started bashing lumps off their finely crafted monument just so that they could decorate the prehistoric equivalent of a mantlepiece.

Re. the fragment found on Silbury Hill....somebody elsewhere has scandalously suggested that Atkinson deliberately dropped a piece to "big up" his excavation there.

It will be interesting to hear what the latest (Aug/Sept) Stonehenge Riverside excavation of an Aubrey Hole turns up.

Jim.