Unknown Copper | Spain 4 Maravedis 1605

Spain, Philip II, AE 4 Marevedi.
Worth about four bucks or so.

Thanks to all.
Whenever I get a piece like this, i.e. Thick lump of copper. Squiggly lines. No definition., my default setting is Spanish.
Which is where the problem starts. SCWC 1601-1700 is good for non specialists like myself in many ways but fails to deal in most cases with low value copper. Illustrations are sparse and descriptions vague.
I don't want to spend too much, but realise I need more references. What books should I be buying? Apart from Spanish, my interests include Italian and German states.