Denmark 1854 Essay

 This stamp is an essay of Denmark made in 1854.  The colour of this proof is brown (with blue underprint). There also exists another essay with the head of Mercury facing the left.

Genuine Stamps

Forgeries

In both genuine essays, the pearls of the central circle enter the space with "K.G.L." in the forgeries they don't.

This one shows the dividing lines typical of forgeries

Possibly a Torres fabrication

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

Albania 1913-1920

 The early stamps of Albania can be quite complicated to ID given the variation of handstamps.

Genuine June 1913 Sc4-11 issues

The key features

In clear impressions the pupil of the eyes are evident

In the genuine, the S has flat top & bottom

Here are various genuine issues

Another way to id genuine issues is by the feet.

Forgeries

The top 2 were sold by Fournier

Nov. 1913 Sc27-33

Forgeries

These were sold by Fournier.

1920 Sc113-120

Genuine Issues

Forgeries

These were sold by Fournier

In the genuine top, the S has a rounded top.

Note discrepancies in other letters and spacing.

Fournier - Stamp Forgery Equipment

In 1917 Fournier purchased all the stock from Mercier (actually Henri Goegg).

Included was equipment to produce stamps. With these and over 100 cliches ( see Blog Francois Fournier - King of Forgers).

https://stampforgeries.blogspot.com/search?q=fournier+king

Fournier was able to continue producing and modifying forgeries. These are photos of this equipment at the Geneva Museum.

Costa Rica - Guanacaste Province

 The province of Guanacaste, claimed by Costa Rica since about 1824 and also by Nicaragua since 1858, was finally awarded to the former by President Cleveland in 1888.
Single stamps overprinted “Guanacaste” showing cancellations from the other five provinces are always fraudulent fabrications.

Genuine stamps

Kohl listing of all the genuine overprints.

Forgeries - Fournier

Typical Fournier Overprints