Mystery marks on plique a jour art nouveau earrings c1900

[Peartree1234]

Can anyone please help identify the marks to these earrings. The makers mark appears to F S, separated by a stylised snake or worm. There is also a gold mark for 750 and potentially another assay mark that looks like a perhaps a stylised bird.

The earrings are rare plique a jour, silver on gold. I think they must therefore date from c. 1900 but perhaps they are more modern. I think the pins, which holds the marks, are original. The lower diamond drops look like they may be later additions from the images but "in the flesh" I think are probably original too.

The earrings are about 5cm x 4cm and are pretty good quality - the blown up image of the reverse in particular is slightly mis-leading. The enamel is pretty refined - better than most German jugendstil work I have seen though not up to French standards for the period.

Best guess is German or maybe Spanish though the marks remind me of a Mexican maker I think but that seems improbable? The earrings most remind me of designs by Masriera who seemed to make earrings around 1900 unlike most makers and also favoured silver on gold. The pointed oval top of the earrings is also like known Masriera designs. Perhaps this is a less well known Spanish maker copying Masriera?

All thoughts welcome.

Thank you and a happy New Year

[Peartree1234]

I have found further marks on the posts. They look like assay marks of some kind but are too small to photograph. A rather feeble hand drawing is shown below. There seems to be on each post two consecutive marks of this form - looks like birds heads but maybe interpreted as birds flying (though to the right, not as for Portugal) or Kiwi/Hen type bird in full. Any thoughts on origin welcome. Thank you

[dognose]

Hi,

Could the "Bird's head" mark be an Austrian import mark (1901-1921)?

See: http://www.925-1000.com/Faustria_02.html

Trev.

[Peartree1234]

Thank you. I wouldn't rule it out but I cant pick out any letters at all, it looks clearly like feathers. If you look at the photo image of the pin I provided and then look above left of the 750 gold mark you can just pick out the "anvil" shape of the mark, though not in the inner "bird" impression. You can see it is quite "sharp/pointed" along the top, more than I drew I think.