The 90p has 4 variants:
1 Orthogonal watermark, line of AЯ vertical, no coating (no tizado); 37.5mm high, printed on the Mailander sheet-fed press:
2 Orthogonal watermark, line of AЯ horizontal, pock-marked coating (tizado varioloso) ; 37.5mm high, printed on the Mailander sheet-fed press:
3 Orthogonal watermark, line of AЯ horizontal, coating (tizado) ; 39.0mm high, printed on the Goebel reel-fed press:
And at last -
4 - the variant without watermark, coating (tizado) ; 39.0mm high, printed on the Goebel reel-fed press.
The Servicio Oficial is nothing but a bi-coloured (ochre and black) photogravure stamp.
1 S.O. Orthogonal watermark, line of AЯ vertical, no coating (no tizado); 37.5mm high, printed on the Mailander sheet-fed press:
The differences in screens:
variant
1 (plus S.O.) and
2 - fine screen:
variant
3 and
4 - coarse screen:
The differences in hight:
variant
1 (plus S.O.) and
2 vs variant
3 and
4:
There remains to be seen whether the variant no 1 (uncoated) exists with differences in the watermark size! The so-called mate nacional vs the mate importado!
to be continued ....