These iron "tools" werw recognized and used as currency. They have been vetted as authentic, from the late 19th - early 20th century.
Additional information on Mambila hoe currenciy 36 with our thanks to:
Dr. Daniel Mato
Professor Emeritus of Art History
The University of Calgary
Calgary, Alberta, Canada
"Asymmetrical flat hoe shape with elongated tang ending in a small loop. This hoe is a commonly recognized form among a number of different people of northern Nigeria into Cameroon and as far as Chad . The hoe also serves as currency for its absolute value as iron and its functional application as a hoe where the tang would be hafted onto a short wooden handle. Known as "Bandaka" in some regions."