Labuan Colour Disturbance

Hi Everyone. I have been checking through some old Labuan stamps and I notice a strange occurrence on some of the stamps. The frame colour seems to vary across the stamp. Could this be an error in the printing or is it more likely a fading of colour since the stamp was issued. The one I am showing is SG100. It is quite clear if you look at '24' on either side.The same phenomenon is also on my copies of SG94 and SG116. Any comments would be most helpful.

Hello. This appears to be oxidised/sulphurised - i.e the original colour has been changed by exposure to sulphur at some point in its life.

I have seen this "dullness of colour" in stamps archived in coin pockets.
Plastics damage.

Can you make the picture bigger, and out of the mount.

I think I see some doubling of PERGO ET.

Thanks for that interesting information.

I mentioned that I have that condition in 3 stamps. All of them have reddish-brown frames variously referred by SG as chestnut, rose-red, or lilac-brown. The centres are not affected, and neither are stamps with different color frames. Must be something in the red / brown mix.

Sharing the other two for you.

For Dynamode ...... I enhanced the dpi and zoomed in. There is a definite double image there.

The 16c has a line and a dot in the lower right corner. As far as I know it is a printers guideline.

I have lots of stamps with lines like yours, from various countries, but have not noticed a dot before. Interesting.

The 24c does appear to have doubling down and to the right. Very noticeable on the O.

There are many re-entries to be found on Labuan/North Borneo stamps.