I do not actively collect Labuan but could not resist the 3c Jubilee stamp with such beautiful chinese characters. It has the wording Tai Chun which translates as "Peaceful Spring (as in season of year)" It was either the name of a chinese company or a chinese association. I was advised by a learned friend that the stamp was probably used to pay revenue charges on a document.
Update: This is probably the chop of a chinese trading company based in Singapore with a branch in Labuan. I have seen the same chop on a Straits stamp with a Singapore postmark.
The same revenue use would also applied to the 5c NB stamp with partly decipherable chinese writing of "fifty one......." I think they are collectable and it would have been very nice to know the background to these stamps and the companies and people who used them. Any info would be appreciated.
North Borneo also provided a club packet system used by the chinese for remitting monies back to their original homes in HK/China. This was to save postage charges as the letters were sent together as a registered parcel. Unfortunately it is unlikely much of these original wrappings with their postal markings and stamps would have survived intact to this day.
My team is working on this one. will update as soon as we have something.