Great this humor

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Beautiful keris and as said here, leave it the way it is. I have some Bugis keris in the same condition. Indonesian people in my neighbourhood told me that the Bugis used their keris as a weapon. The warangan treatment was done with the delivery and the only treatment for a Bugis blade was cleaning with lemon juce wich faded the high contrast of the warangan treatment away during the time.
This in contradistinction with the Javanese/Balinese/Madurese societies where the warang treatment was done regurlary.
This confirms what is said here.