New Caledonia 1859 10c black

 1500 were issued. 

This stamp was seldom used and some specialists question if it was used.
Many forgeries exist. Genuine stamps were printed with black separating lines, and thus only the outside borders can have white margins. 
There are 50 different types of this stamp, so it can easily be identified on the full sheet.

Genuine

This is the original sheet

Position 6

Postion 43

Forgeries

Forgeries have too many white margins

Moens Forgeries

Moens 1864 catalog impressions

Many forgeries were paterned after Moens.

Reprints

Note the title in English instead of French