Twelve lok keris

[GIO]

Dear Friends,
first of all I wish to introduce myself as a new member of this forum.
I live in Milano (Italy) and have been collecting keris and some other Indonesian weapons since 1985. I hope we shall have fruitful and interesting discussions in future.
Now let's come to the topic.
I have been told by a well-known person (great collector and writer of books and articles on keris and keris hilts) that, as the sole exception to the rule of odd number, that 12-luk keris do exist. The number twelve would have a particular significance for the malay people (don't remember which).
Of course such keris are extremely rare and high valued.
Anybody wish to comment ? I have no further information.
Thanks in advance to everybody.