So, I just visited St. Mark’s basilica and was quite amazed at the ceiling’s beauty.
I was somewhat surprised to find that the internet does not seem to list how many tiles make up the extensive ceiling mosaic. Several places list it as having 6,000 square meters of tiled ceiling (those Italians and their silly metric units!). This translates into 64,583 square feet or 9,300,018 square inches.
Trying to recall, I would hazard a guess that the average tile was about a quarter inch (that’s 6.35 mm for you Italians) on each side. But truly, I have no idea how big they were. Assuming my guess is accurate, this translates to about 37,200,000 tiles
Does anyone else have a better guess or more information?
Why would that information be available? They may have had available at some point the information needed to figure out how many tiles were made (I’m guessing they were made rather than purchased, or at least made to order, based on what little I know about building methods of the times), but mosaics use broken tiles as well as full ones, and not every tile is the same size. It’s not like the tiled floor in a house, with machine-made tiles all laid out beside each other in a regular fashion.
Of course I don’ t think they have an exact count. Its just like every other impressive work. Wikipedia lists a number of blocks in the Great Pyramid of Giza (yea, its Wikipedia, but you get my drift). They didn’t count every one, they did some measurements, counted some representative samples, and then made some scientific WAGs.
You might try a search on teh googz with better jargon: tesserae (the mosaic cubes in Byzantine technique-- tiles ain’t the right term to work with) and San Marco. Someone might mention the average size they were using in the lagoon in those days. Then you’ll have to decide if you want to count mosaiced wall surface just in the core of the church or also the narthex/side rooms like the sacristy/exterior (and on that note, original tesserae or including 16th/19th/20th-century interventions). You are never going to get closer than an extremely approximate number.
Nava, in this time/area they would make sheets of glass (there was a glass foundry on Torcello-- probably one in Venice, too) and then break the sheets into pretty regular chunks (the problem here is that the mosaics were done over a range in time and there might not be a general standard). Some might have been broken but not standard-- they didn’t do the pebble mosaic thing like the old Greeks and old Romans did. But still. Ok, 37,200,113. There we are.
When we visited St. Marks, 3 of the mosaic tiles fell off the ceiling and hit my wife on the head. All three were gold colored/gold-leaf? and are nearly perfectly square (1 cm x 1 cm). We approached 2 docents with them and neither had any idea what to do with them so we still have them. They are about 2-3 mm thick and the “backside” is pitch black.
That’s a great story, Disheavel, but can I recommend that you do a little digging as to the people in charge and see about sending them back? Every little piece of a monument like that deserves to be protected. I’m sure they’d appreciate it, especially if you can point out more or less where they fell from.
(Incidentally, did you know that St. Mark’s wasn’t the cathedral of Venice until comparatively recently? Up till then, it was officially the private chapel of the Doges’ Palace and the official seat of the bishopric was a monastery church some distance to the east.
There is also a former cathedral on the all but abandoned island of Torcello, dating back to the time when Torcello was giving Venice a run for its money as the main city of the lagoon, up until an unfortunate episode with the plague, IIRC. I visited it – it’s decayed and very calm and beautiful. Only about forty people still live there, but it does a small tourist trade and the vaporetti run out to it.)
You are right. I was thinking 1/2 inch which would make 4 to each square inch, but then I carefully wrote (and converted) the 1/4 inch measurement.
Obviously Disheavel’s 3 data points are far from a complete representative sample, but it is what we have to work with. Using 1 cm squares, that would imply ~90,000,000 tiles, uh er, tesserae.
Would these figures take into account mortar? Granted, it’s minimal but over the course of some thing this large, it’s bound to take effect. Not that it really matters, I suppose, but I know how Dopers love a challenge like this!
I was actually looking at a detail photo and wondered this last night. I think it could be as much as 1/6 or 1/5 of the surface area might be plaster/cement/whatever between tesserrae.
I second this. Disheavel, you should probably contact the office for the Patriarchy of Venice: http://www.patriarcatovenezia.it. They’re in charge of the art and architecture of Venice’s churches (I found this out recently, when I had to contact them to acquire reproduction rights for a few altarpieces and other paintings in church collections in Venice).
As for the OP, I doubt if it’s possible to calculate the total number of tesserae at San Marco. The tesserae tend to be irregular in size–for instance, if you look at a detail of a saint’s face, you’ll see lots of small tesserae forming the various facial features, but when you look at the gold background, it will be comprised of fewer but individually much bigger tesserae. Furthermore, you’re dealing with several different mosaics created at various times in the church’s history, from the twelfth century through the Renaissance–some of the mosaics on the exterior are even later (the big one of the Last Judgment, over the central door on the west facade, was made in the 19th century). The different styles demand different sized tesserae (the Renaissance and later mosaics feature a lot more modelling and perspective, and are actually a bit jarring with the earlier Byzantine mosaics).
Thanks for the website. They are investigating what they want me to do. We did make a good faith effort while there, but I’m getting the impression that it happens a bit more often than what one would think.