The
'furr lines' you mention would mean the engraved portions of the stamp
which do show up in your stamp on the bottom.
The stamp was a combination print of engraved and photogravure.
Most forgeries are usually just offset/litho.
Here below is a scan of a genuine monkey stamp which was owned by
a former member here ,Galeoptix who received
four of these stamps
from his missionary aunt visiting China in 1980/81
They look as real as any I have seen over the years.
Notice the vertical inkflow of the red background which indicates photogravure
printing. If the background is a solid colour then it is a fake offset printing.
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The gum side of the four owned by Galeoptix
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