Mystery coin with unusual counter mark

Hi folks 

begging for assistance again… just received this possible 16th century European coin with an unusual counter mark/stamp. Any clues Would be much appreciated! With thanks Adam 

5.96gm

30mm at widest 

not sure if billon or bronze type 

Looks like a sextant.

Or else it's the combination of a cross, sickle, and sabre or cutlass.

Perhaps it would be possible to find this symbol somewhere in historical documents, and therefore identify the countermark, but it would be a very lucky find indeed. Most such countermarks (i.e. old images or symbols) are never identified.

It helps that this is a good quality countermark produced with a good quality punch. With some luck other coins or metallic objects might be found with the same mark.

We might not be able to help with the countermark, but perhaps we can help with the coin itself. The legends on both sides seem to indicate some variation of the 2 maravedis coin of Ferdinand and Isabella (Elisabet in Latin) in their capacity as rulers of Castile. Although I don't know why the date range is listed as 1520-1566 on the Numista page; it should be 1474-1504 when speaking specifically of Castile.

N#48590

Thanks, this is a very useful pointer and i will dig deeper next! kindest regards Adam