Folding knife - looking for information

[fernando]

Spanish author Rafael Forton reminds us that the term NAVAJA comes from NOVACULA, meaning (in Latin) nova, as for renewing, or making new, referring to the act of shaving.
The missing link, being a transitional specimen or specimens connecting the ancestor razor blade to 'modern' navajas (folding knives) must be jewels to collectors.
An hypothetical approach to such thing is shown in his work LA NAVAJA ESPAÑOLA ANTIGUA (so often quoted in this forum), in page 24, estimated to be from the 17th century.
I would'nt mind considering Ypoznan's old (ancient ?) example worthy of certain importance.
I wonder what Navaja enthusiasts like Chris Evans think about this piece.

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