Greetings all,
About a year ago, when this all first hit the news, a friend of mine
and I started doing some research into reproducing the inlay. (Tom,
if you’re reading this, please chime in.) Unfortunately, I got
sidetracked by moving, so I’m just now getting back to where I can
continue with reproducing it.
What we discovered is that there are a variety of very good, and
very obscure treatii on the subject. Saint Birgit the Unpronounceable
being foremost among them. (Birgit Arrhenius, Merovingian Garnet
Jewelry being probably the best. ) There are a bunch of good
articles scattered around in various publications, including a couple
in Anglo-Saxon Studies in Archaeology and History, vol. 4 dealing
with cutting the garnets, and making the foil for the inlay.
We got a bunch of garnet rough in various shapes, to try cleaving,
as it looks like it has nice, clean, obvious cleavage planes. No
dice. It may look like it’ll cleave nicely, but it doesn’t. (Or if
it does, please somebody tell me how!) (Tried knife blades, hot and
cold, thermal shock, every trick I could think of. Gravel every
time.)
That was about as far as we’d gotten, before I got sandbagged. I do
a lot of work with making gold foil for damascene work, so making the
gold foil presents no particular challenges. We were more worried
about cutting the rocks than what to do once we had them.
In looking at the period examples, it looks like there were a
variety of techniques in use, depending on the quality of the work.
First, the scholarly work makes a pretty convincing argument that
there were cutting centers in modern Germany and Bohemia that made a
majority of the ‘rough’ plates, which then were sold on as rough
preforms, to be finished to shape by whoever did the final work.
Equally, it seems like a good bit of the garnet used was Bohemian in
origin. (makes sense.)
The setting could be done in one of several ways, depending on skill
& quality. The Sutton-Hoo pieces are probably just friction fit, with
nothing behind them. (cut the stones to fit the cells-exactly-, and
then cut a bit of gold foil ever so slightly bigger. Place gold foil
under stone, and over cell opening. Put stone on top, press in. The
gold will wrap around the stone and add a bit of friction to hold it
in place. That’s it, and it’s held for 1400 years. The problem with
basing anything on the Sutton-Hoo pieces is that they’re so well
made, and in such good condition that it’s really hard to figure out
what’s going on. There may have been some paste behind the stones as
a backstop originally, but there’s no way to be suRe: most of the
stones are tight, so there’s no way to see what’s behind them. Also,
the soil at Sutton-Hoo is so acidic that it may well have dissolved
any organic paste originally present. (It did dissolve the body they
were buried with.) There are repair holes in some of the pieces,
showing where holes were drilled from the back, and the stones were
poked out, which probably wouldn’t have worked if there’d been any
paste there originally, but that’s a matter of opinion. (The paste
being more like pitch, than wax so it would act like a solid glue,
rather than a wax that you could push a pin through.) (Think
setter’s cement, or dopping wax, not beeswax.)
The ‘second rate’ settings seen in other garnet work did have
paste filling the cells as a backstop. Sometimes just the paste and a
friction fit with the gold foil as a ‘caulk’, were enough to hold
the pieces together.
The ‘third rate’ version was to have the cells filled with paste,
and the gold foil, and then burnish the top of the cell walls in a
sort of rubover setting. I say third rate (my term) because the
rubbed over type setting gives a much messier look. The walls are
wider (much) than the high quality settings, and they tend to wobble
visually. Straight lines ripple, and right angles aren’t. The stones
also tend not to be as tightly cut in that level of work.
I’m really looking forward to getting a better look at the
Staffordshire pieces once they’re conserved (or even just washed
off!), as there are pieces in a wide range of quality levels
represented. And while it stinks for the pieces themselves that
they’re as badly broken up as they are, it’s an invaluable glimpse
into the techniques of their manufacture that they’re not in nearly
perfect condition like the Sutton-Hoo pieces.
For whatever that all’s worth,
Brian.