I have read here:
http://www.myArmoury.com/feature_oakeshott3.html#pommelG
Here the date is pommel G after 1400 G1 second quarter of the 15th century.

I have read Sword in the Age of Chivalry. On a blade X or XI were found pommel Type G.
That's the theory.

In practice I have seen a sword excavated, the blade maybe an Xa or XII at a museum, which had not yet shown. Pommel was no "G" no "H" no "I".
Let me explain, was a disc without bevel, without concavity. Just a round flat disk, oddly small in size.
How to classify this type? perhaps "G" without concavity?

One other question. If I have an sword archetype: a blade type "Xa" must have a pommel type B or H. Type G is perhaps less well. Am I right?

One other question: I have read: Many swords of this type are represented in the Bayeux Tapestry. The pommel type was type "G". How do you say this? Is more likely to have type "H" .
I apologize. Too many questions.

Hi Maurizio,
I hope I understand your questions correctly. Type G is typically a flat disc with no bevel or concavity (though often it does have a slight convex bulge in the face like the drawing). What Oakeshott said was that it was extremely common in all stages of the Medieval sword. The reference to the concavity was that in the 1400's, if the pommel type appeared, it often had a concavity, not that the type always was concave. Therefore, the swords in the museum that have flat discs have the more common variety of type G.
As far as it not being appropriate to have a Xa or XII with a type G....those would be perfectly acceptable. As I said before, type G is found throughout the medieval period (though perhaps more common earlier). Oakeshott had not yet created the Xa type in his Sword in the Age of Chivalry, so he wouldn't have mentioned it.
Finally, the swords depicted in the Bayeux tapestry are most likely type G.
I hope this helps and that I'm expressing things clearly,
Dan

Thanks Dan,
you've hit the point. :)

Even if we can find an pommel type G (with the convex) in the period 1000-1300, we can say that the most common type G was without concavity.

On the contrary from 1400 onwards is more common to find them with the convex.

A archetype for a blade X is better that pommel is flat or slightly convex.
If I understood the answer to my question is complete.