Biff the unclean

The oldest ones the Vatican has with dates in them come from 325 CE. I don't know about private collectors.

As I understand it paleographic comparison is done by taking a separate manuscript of known date and comparing the styles of script with what you have. Script written by a different scribe.
It seems to uneducated me that the most this could possibly do is give you the earliest possible date. You couldn't write in a script style before it was designed. But once it is designed it doesn't go away.
These fragments of John are truly fragments, tiny scraps with only a few partial lines of text. So there is nothing to spare to do any carbon dating with. There were no major advances in parchment, papyrus, pens or oak gall inks at that time nor for hundreds of years after. The codex was invented but these scraps are too small to tell if they are from a scroll or not.
But the handwriting looks similar to the handwriting of someone else who lived in 125CE. It is not unusual for handwritten Bibles of today to be done in calligraphy from the Middle Ages. Not with any intent to deceive, but out of reverence for the text. One wonders what paleographic comparison people in the future will make of these 21st century Bibles.

Vorkosigan

You mean like "Dated this thirteen year of the reign of Emperor X?" Now that's an interesting question. Are there even any? Were medieval scribes in the habit of dating their copies?

Vorkosigan

Haran

Exactly.

I know I've read that there are some like this, but I can't remember which ones, and I'm not sure what the earliest one(s) is(are).

CX

Since when? I'd have to check THTNTW but I thought it said in there that it was "no longer certain" that's not quite the same as "no longer viable". Still it's probably quibbling. My general impression is that most of the early dates (i.e. 1st half of the 2nd century) are confessionally motivated to some degree. Plus I've never seen a good presentation of how paleographers can narrow a range to within +- 25 years.

CX

Heh. That's what happens when you turn your back. You take a shiv right in the ribs.

I haven't seen that but I'd be interested to.

CX

It's unlikely it was a scroll. The lineation is consistent with codices of the time plus it's written on both sides.