1970s European brutalist silver and chrysoprase Ring

It is always vexing when a hallmark eludes identification and this is (almost) the case with the towering vintage silver ring at hand. Brutalist in design, having a big, semi-translucent chrysoprase cabochon nested in its elevated setting, it bears a partial hallmark which has been suggested to me is probably a maker’s mark from Spain. Home of renowned modernist designers such as Joachim S’Paliu and Puig Doria, Spain sounds like a plausible place of origin for our 1970s ring…

Size / Weight: sz 6 US (adjstbl thanks to its open shank); face is 13/16” in diameter; just above 1/2” rise; 12.3 grams

Hallmarks / Date: partial hallmark showing what I read as a “C” above a “3”; tested and guaranteed to be solid silver of at least .800 purity though most probably sterling; 1970s

Condition: excellent vintage with a dramatically textured and oxidized setting, captivating presence, a beautiful stone, great patina and no damage or repairs noted

Inv# 15563