Souvenir Sheet is square format.Although this edition was authorized by the Niger postal administration, it was not sold in Niger, but only distributed to the novelty trade by the Nigerian philatelic agency.
Also in the issue Minerals (2018.2):
Data entry completed
|Souvenir Sheet Phosphophyllite in digits|
|Face Value:||3,300 West African CFA franc|
Souvenir Sheet Phosphophyllite it reflects the thematic directions:
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