According to Greg
Weisman's vision, the peculiar phenomenon of gargoyles' possessions
turning to stone resulted from a wizard's spell in Roman times.
The problem was this: whenever humans came into contact with
gargoyles, they were shocked by their nudity. The gargoyles,
of course, saw nothing wrong with this. If they had ever tried
to wear clothes in the past, they soon abandoned it because it
just wasn't worth the trouble; whenever they turned to stone,
their clothing stayed the same, and shredded to bits when the
gargoyles awoke at sunset.
As gargoyle-human contact increased,
gargoyles tried to wear clothes so as to appear more "respectable".
I think you can guess that this wasn't successful. So some Magus
around the 1st century ad (supposedly the original Magus) cast
a spell that somehow applied to every gargoyle everywhere. From
that night on, a gargoyles' clothes and/or anything they considered
a personal possession would turn to stone with them and be restored
at sunset along with the rest of the gargoyle.
And so that's the basic history of it
for those who didn't know. Now, how far can this go? Well in
"Awakening" we saw that Goliath's bandage (on his hand)
did not turn to stone at dawn because it was not a personal article,
it was only temporary. Demona's skimpy outfit remained relatively
fresh over the centuries because it was restored like new every
night. Broadway in "The Green" held the sun amulet
when he turned to stone, but it did not. In general, most shots
in the show have gargoyles fully stone, possessions in all. One
exception that doesn't seem to make sense, but which is most
likely an animation error, is that Hudson's sword doesn't always
turn to stone when he does, yet it is a personal possession.
Watch the show carefully and you'll see what I mean.
In sum, anything that the gargoyle
is not particularly attached to, or that is very newly acquired,
will not turn to stone, so obviously there is some sort of time
element built into the spell; my question is, how does the spell
decide what will become stone and what will not?