where have all the ganjas gone?

[David]

As Kai has mentioned, the gonjo can experience a bit of wear and many times they simply break after time, especially if the keris has received regular acid treatments.
It should be understood that gonjo iras keris are not blades without gonjo, but rather a blade where the gonjo is incorporated into the blade which is made all as one piece. Sometimes with gonjo iras keris a line is engraved to mark where the gonjo begins, but many times it is not. This does not mean the gonjo is non-existent. The difference between a gonjo iras blade and one that is simply missing its gonjo should be clear upon a close examination.
I have heard various philosophies surrounding the gonjo and its purpose, both practical and mystical. But i would suspect that the stories you were told about orienting the gonjo at an angle for magickal or martial arts purposes are simply tales told to justify when a gonjo has come loose.
My understanding is that a keris without a gonjo is incomplete and for a blade that is in use within the culture a new gonjo would be forged as a replacement. I would image such a task is less likely to be undertaking out of culture in the Netherlands.

[A. G. Maisey]

This "no gonjo" problem sounds to me like a uniquely European or maybe uniquely Netherlands problem,yes, certainly I do come across the occasional keris missing a gonjo, but this is very, very occasional.

In Jawa & Bali gonjos normally get replaced when they go missing, for whatever reason. In Australia I doubt that I have ever come across a keris with a missing gonjo, I might have, and have forgotten it, but there are not a lot of keris floating around in Australia in any case.

As for the stories that appear to accompany missing gonjos, I suggest that these should be taken with a very large grain of salt.

[Athanase]

I have the same gonjo problem in France. Fortunately, this is far from being the case for the majority of keris that I see, but it is regular.