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That does seem to always be the question when we encounter keris that claim to be complong (combong), is it true complong?
For my money to be assessed "true", complong must be a matter of intentional forging. So this rules out holes in sogokan worn through by years of acid washing or slits in the blade from weld failures.
When i look at yours i'm on the fence a bit. The slit in the blade does seem to trace along a weld split. But if that is the case it appears to have been widened and made large on purpose. I suppose it is possible that this open seem was always in the mind of the smith from the get-go. Or it might have been ab after-thought. The weld failed, he couldn't fix it, so he made the best of it and enlarged it to look intentional. Another possibility is that this weld failed after a time and someone came along and decided to make the best of it and turn this into a complong blade. I don't think knowing for sure is possible, which brings us back to belief, a concept upon which many assessments in the keris world are based.
