Green light/smoke speculation - not the cover though

[kjirstem]

No: HPFGUIDX 125852


Speculation about the greenish light on the Scholastic cover for HBP
has reminded me of a nagging question I've had for some time. 

When Harry's Gringotts vault is first opened a lot of green smoke
billows out. There is no mention of a similar effect with the vault
the Stone was in. This seems strange to me and I've wondered if it was
significant at all, perhaps associated with the events at Godric's
Hollow. I've just posted about this OT Chatter too but have come
to believe that any discussion about it on-list has been in the
distant past, so I'm bringing it up here.  If anyone has the
whereabouts of previous discussion, please let me know. 

In any case, I don't have anything that I'd call a theory
about the green smoke, but a few things have occurred to me:

1. Somehow it is associated with the AK curses and/or destruction of
the Potter's home,

2. It is some Gringotts enchantment, for security?

And

3. Somehow the coins weren't in the vault until the door was
opened and the smoke is an effect of whatever means by which they
appeared.

I guess 2 and 3 could be related, but I've always leaned towards 1
anyway.  The thing is, how could there still be green smoke in the
vault after so much time?  

I suppose the green smoke probably means nothing but it has been
niggling at me for some time and I wondered if anyone else had
thoughts about it.

kjirstem